Planet X: MAY Coordinates [OT]
Nancy Lieder
> Again, the nature of the object doesn't matter. If
> Nancy says it's magnitude 2 (or 11 or 7 or whatever
> today's lucky number is), then that means it has a
> certain brightness, whether it's a star light-years
> away, a light bulb just across the street, or a planet
> somewhere between.
And you can see them ALL, presumably, no matter what their distance, no
matter what the limitations of your eye may be re color spectrum, no
matter what your equipment is set to use as a trigger, or what intensity
of light is required to register an image in this equipment. Did you
see the last Mar's probe, then, when it disappeared, got lost? Can't
find it? Surely it reflected sunlight. Too small you say? Your scope
does not zoom, to magnify, so it would be too small? Not enough light,
from such a tiny object, to register on your equipment? I thought this
didn't matter!
Greg Neill
news:3AFB4030...@zetatalk.com...
Visual Magnitude is not like the wattage of a lightbulb. It
doesn't say how bright an object is intrinsically, but how
bright it is apparently, that is, as actually viewed in the
visible spectrum.
One can calculate the visual magnitude of an object from
its albedo, size, and distance from the source of light
(in this case the Sun). If the object has a low albedo,
or is very small or very distant, its visual magnitude
may be too low to see, particularly if its light is
lost in the glare of a much brighter, close-by object.
If the object is shining by its own light, then the
same fact remains -- the magnitude specifies how bright
the object appears as actually viewed.
If you begin by stating the visual magnitude of an object,
say 2nd or 11th magnitude, and if said object is isolated
in the field of view, then it must be visible at the
stated magnitude. To say otherwise is a contradiction.
DC
Oh Nancy,
If you have claimed that an object is at a certain magnitude,
then you are describing how bright it appears here on earth.
The distance to the object is immaterial. You are not describing
its luminosity, but the intensity of the light at the detector
on earth. Your above post is clearly in error due to your
misunderstanding of this subject.
--Donna
tho...@antispam.ham
> Did you see the last Mar's probe, then, when it disappeared, got lost?
> Can't find it? Surely it reflected sunlight.
Why are you using the past tense? It still reflects sunlight, whatever
is left of it, whenever it is not in the shadow of something else.
> Too small you say?
More important is the distance. You do know about the inverse square
law of light, don't you?
> Your scope does not zoom, to magnify, so it would be too small?
Irrelevant, given that magnification can't make something brighter.
> Not enough light, from such a tiny object, to register on your
> equipment?
It can register all right, but not at a sufficient level to
distinguish from the noise. Ever listen to a radio station as
you drive farther and farther from the transmitter?
> I thought this didn't matter!
You thought wrong. Again.
Nancy Lieder
equipment limitations, etc.) and it’s pie in your face! This is all OK
for the Mar’s probe, but not Planet X? Substitute Planet X for the
Mar’s probe in David’s defense, and he’s made my argument. I’ve done
this, below.
And re your statements that an object smaller than Pluto is not being
able to be “diffuse”, this is also a silly argument. Diffuse applies to
the overall appearance of whatever surface is visible. A tiny mite can
be “fuzzy” if covered with hair, and just because to you it looks like a
dot does not mean it’s not fuzzy! I’m sure, to the Hubble, Planet X is
diffuse. To the amateur astronomer, the fact that it does not have an
intense pin-point of light as do stars makes it more difficult to find
and to view. This is why it is being recommended that:
1. look at the Zeta coordinates given, and look AROUND that spot as well
2. use a scope that can MAGNIFY (zoom) as observatory scopes do
3. filter FOR the red, as this will differentiate Planet X from the
surrounding sky
4. look for a DIFFUSE light over the surface, not a pinpoint of light
(MAG 11 in equipment)
In Article <vnRK6.3690$n81.1...@typhoon.hawaii.rr.com> Davide Tholen
wrote:
> Nancy Lieder writes:
>> Did you see [Planet X], then, when it disappeared, got lost?
Gar...@truss.net
<zeta...@zetatalk.com> wrote:
>OK, David, apply your argument to Planet X (size, light reflection,
>equipment limitations, etc.) and it’s pie in your face! This is all OK
>for the Mar’s probe, but not Planet X? Substitute Planet X for the
>Mar’s probe in David’s defense, and he’s made my argument. I’ve done
>this, below.
>
>And re your statements that an object smaller than Pluto is not being
>able to be “diffuse”, this is also a silly argument. Diffuse applies to
>the overall appearance of whatever surface is visible. A tiny mite can
>be “fuzzy” if covered with hair, and just because to you it looks like a
>dot does not mean it’s not fuzzy! I’m sure, to the Hubble, Planet X is
>diffuse. To the amateur astronomer, the fact that it does not have an
>intense pin-point of light as do stars makes it more difficult to find
>and to view. This is why it is being recommended that:
>
>1. look at the Zeta coordinates given, and look AROUND that spot as well
Why look around? Aren't the coordinantes any good?
>2. use a scope that can MAGNIFY (zoom) as observatory scopes do
You fail to understand how telescopes work. You have proven this
MANY,MANY times through your rediculous postings.
>3. filter FOR the red, as this will differentiate Planet X from the
>surrounding sky
Nonsense.
>4. look for a DIFFUSE light over the surface, not a pinpoint of light
>(MAG 11 in equipment)
See above, i.e. no understanding of telescopes.
Wait, what am I doing....
*PLONK!*
Enough of this bullshit.....
Greg Neill
>
> And re your statements that an object smaller than Pluto is not being
> able to be "diffuse", this is also a silly argument. Diffuse applies to
> the overall appearance of whatever surface is visible. A tiny mite can
> be "fuzzy" if covered with hair, and just because to you it looks like a
> dot does not mean it's not fuzzy!
Surface texture is irrelevant if the object is viewed from a
distance such that it is indistinguishable from a point source.
All of the light being emitted from the object in the direction
of the observer will arrive at a single observed point image.
> I'm sure, to the Hubble, Planet X is
> diffuse. To the amateur astronomer, the fact that it does not have an
> intense pin-point of light as do stars makes it more difficult to find
> and to view.
According to your own data (size and distance), it must subtend an arc of
about 10^-5 degrees as viewed from Earth. That's essentially a point
source, and would be so to Hubble as well.
Larry brown
Greg Neill wrote:According to your own data (size and distance), it must
subtend an arc of
> about 10^-5 degrees as viewed from Earth. That's essentially a point
> source, and would be so to Hubble as well.
Hello Greg,
What sort of scope do you use for planetary viewing? Do you prefer a
reflector or refractor.
Just wondering.
L Brown
Greg Neill
news:3AFC2591...@fuse.net...
I find that a refractor does a fine job for planetary viewing.
I have a small Meade which I drag out every now and then, but
truth be told I'm more 'into' the theoretical side of things,
particularly orbit simulations and the like.
da...@pebble.org
TangoDe...@fuse.net> wrote:
> What sort of scope do you use for planetary viewing? Do you prefer a
> reflector or refractor.
Starting a war, are you Larry? I prefer reflectors. I've never seen a
satisfactory view of anything other than the moon through a refractor,
and that includes the 24" refractor at Lowell Observatory in Flagstaff,
Arizona. Most refractors are just plain too small to bother with.
The ones that are large enough are too darned expensive.
- Dan
Bob May
a lot different than seeing that object against a background of about the
same brightness. For reference, take a white pillow and put it against a
black sheet and a white sheet and which background can you see the pillow
easier.
Since you have no idea of resolution, contrast and other such things, you
are so far out of the water of your knowledge that you can be considered to
be an idiot!
--
Bob May
Remember that computers do exactly what you tell them to do, not what you
think you told them to do.
Ken Cox
> Did you see the last Mar's probe, then, when it disappeared, got lost? Can't
> find it? Surely it reflected sunlight. Too small you say? Your scope
> does not zoom, to magnify, so it would be too small? Not enough light,
> from such a tiny object, to register on your equipment? I thought this
> didn't matter!
Then, as usual, you thought wrong. Magnitude *is* the
amount of light, and does matter. A given telescope,
used in a particular way (e.g., putting your eye at
the focus, or putting a photographic plate there for
a couple of hours) will only detect objects brighter
than some given magnitude.
Magnitude 11 is fairly bright, as these things go, and
readily detectable with the eye through even modestly
sized scopes. Magnitude 2 is of course visible to the
naked eye. So, whichever your planet is supposed to
be, it *should* be visible. But it is not.
As for the Mars probe, the magnitude of bodies that do
not emit light is a function of their size, distance,
albedo, and some other factors. For bodies that are at
about the same distance from both the Sun and the Earth
and have about the same albedo, magnitude depends mostly
on size.
Here is a little table of four bodies, all at about the
same distance from the Sun and Earth, and all with about
the same albedo. Fill in an estimate of the missing
number:
Body Radius (km) Magnitude
------------------------------------------
Mars 3400 -2.0
Phobos 10 11.3
Deimos 6 12.4
Mars probe 0.005 ????
By the way, please note that amateurs are quite able to
see Mars' moons with their telescopes, even though they
are dimmer than magnitude 11.
--
Ken Cox k...@research.bell-labs.com
tho...@antispam.ham
> OK, David, apply your argument to Planet X (size,
Which size, the "smaller than Pluto" size or the "diffuse" size?
> light reflection,
Which light reflection, the one that doesn't reflect light or the
one that refers to red iron dust?
> equipment limitations, etc.) and it’s pie in your face!
Not at all. Rather, the pie is in your face.
> This is all OK for the Mar’s probe, but not Planet X?
Did Planet X crash into Mars? If not, then there is no comparison
here.
> Substitute Planet X for the Mar’s probe in David’s defense,
That would be a ridiculous substitution, unless you're prepared to
argue that Planet X crashed into Mars.
> and he’s made my argument.
Balderdash. Has anyone gone to a telescope and claimed to have
seen Mars Climate Orbiter or Mars Polar Lander?
> I’ve done this, below.
Well, it doesn't surprise me that you engage in the absurd.
> And re your statements that an object smaller than Pluto is not being
> able to be “diffuse”, this is also a silly argument.
On your part.
> Diffuse applies to the overall appearance of whatever surface is
> visible.
There is no resolvable surface to be visible. Pluto is only 0.1 arcsec
in diameter, so something smaller than Pluto will be smaller than 0.1
arcsec. You'd need something like a 40-inch telescope to have a
diffraction limit less than 0.1 arcsec at visible wavelengths, and
you'd still have atmosphere seeing as the limiting factor.
> A tiny mite can be “fuzzy” if covered with hair,
Not if you look at it from miles away.
> and just because to you it looks like a dot does not mean it’s not
> fuzzy!
The problem is that the intrinsic fuzziness is not resolvable. That
means you can't see it. And matters only get worse as you go to the
longer wavelengths that you've recommended. A feather is still a
feather, but once it's below the diffraction limit, you can't
distinguish it from a pencil. It's a fundamental limit of optical
systems, which is something else you don't understand.
> I’m sure, to the Hubble, Planet X is diffuse.
To Steve Havas and a couple of others, Planet X is also diffuse,
which means it can't be smaller than Pluto, yet you said it is.
That is a fundamental discrepancy.
> To the amateur astronomer, the fact that it does not have an
> intense pin-point of light as do stars makes it more difficult
> to find and to view.
Then it can't be smaller than Pluto.
> This is why it is being recommended that:
>
> 1. look at the Zeta coordinates given,
When? You still haven't specified the temporal reference frame.
> and look AROUND that spot as well
Just how much?
> 2. use a scope that can MAGNIFY (zoom) as observatory scopes do
Actually, many "observatory scopes" do not "MAGNIFY (zoom)".
Magnification is simply the ratio of the focal lengths of the
primary and the eyepiece. Simply changing the eyepiece to one
with a different focal length can change the magnification.
There are more amateur telescopes designed to change eyepieces
than "observatory scopes". The latter rarely have eyepieces
nowadays. They hang a CCD camera at the focus and get whatever
image scale corresponds to the focal length for that focus.
> 3. filter FOR the red, as this will differentiate Planet X from the
> surrounding sky
> 4. look for a DIFFUSE light over the surface, not a pinpoint of light
Still contradicts your claim that it is smaller than Pluto.
> (MAG 11 in equipment)
You still haven't explained why it was supposedly magnitude 2 back
in the Hale-Bopp days.
>> More important is the distance. You do know about the inverse square
>> law of light, don't you?
Note: no response.
>> Ever listen to a radio station as you drive farther and farther
>> from the transmitter?
Note: no response.
Larry brown
found that each has their strengths and weaknesses. It is dangerous and
illogical to make blanket statements about any of them. In general, your
comments are correct. Good refractors (apos) are prohibitively expensive.
I use my 10" for most viewing, and haul out the 6" achromat refractor for
a change of pace or for lunar viewing. I've always felt that a serious
observer should own one of each. Thanks for your comments.
Larry Brown
Larry brown
>
> Remember that schizophrenics do exactly the opposite of what you tell them
> to do, not what you
> think you told them not to do.
:-)
Paul
size significantly. I recall seeing a documentary by Warner Brothers, I
believe (it must have been produced in a slipstream time vortex, as I saw it
more than twenty years ago) where Planet X was discovered by two rival
parties, who, while chanting the mantra "This planet's not big enough for
both of us!" proceded to destroy it utterly, leaving only a small cinder
just barely large enough to hang on to. Perhaps this is what Nancy means by
diffuse, as most of the planet has been/will be vaporized. If it hasn't been
vaporized yet, it should still be fairly easy to distinguish by the large
"X" labelling it on a planetary scale--perhaps the red filter allows the
label to be more clearly seen, allowing an easier distinction between this
planet and Rev. Farakahn's mothership, which is no doubt also in the area...
"DC" <dcinc...@home.com> wrote in message
news:3AFB5B67...@home.com...
Nancy Lieder
wrote:
> Pluto is only 0.1 arcsec in diameter, so something
> smaller than Pluto will be smaller than 0.1 arcsec.
> You'd need something like a 40-inch telescope to
> have a diffraction limit less than 0.1 arcsec at visible
> wavelengths, and you'd still have atmosphere seeing
> as the limiting factor.
Do observatories view Pluto? I assume yes. What do they see? If so,
then they can view Planet X. Pluto is reflecting sunlight, Planet X
does not but has its own diffuse glow. I quote from my rediculously
outdated and silly book, The Solar System, a Practical Guide (insulted
ahead of time to save David Tholen time):
.. 1978 when Pluto's moon was found. Work on the
orbit of Pluto had been continuing at the United States
Naval Observatory since 1930 in an effort to refine still
further the pertubations in the orbits of Uranus and
Neptune and to find, if possible, a tenth planet from its
effect on the orbits of the outer planets. To this end, a
set of high-resolution plates of Pluto were made using
the USNO's 155 cm reflecting telescope at Flagstaff
over three nights in April and May 1978. ... The image
of Pluto had a bulge. ... With confirming observatorions
being made with the 3 m Cerro Tololo telescope,
Harrington calculated that the moon had a period of 6
days 9 hours and was 20,000 km from the surface of Pluto
... Pluto was found to have a mass of .0002 Earths.
The Zetas have stated that Planet X has 23 times the mass, and is 4
times the diameter of Earth while at 18.74 Sun-Pluto distance. Van
Flandern, during the search for Planet X in the early 1980's, stated he
computed it to be up to 5 times the size of Earth while at 50-100 AU to
account for the perturbations in the outer planets. I quote:
Astronomy, Dec 1981
Search for the Tenth Planet
Astronomers are readying telescopes to probe the outer
reaches of our solar system for an elusive planet much
larger than Earth. Its existence would explain a
160-year-old mystery. ... The pull exerted by its gravity
would account for a wobble in Uranus' orbit that was
first detected in 1821 by a French astronomer, Alexis
Bouvard. Beyond Pluto, in the cold, dark regions of
space, may lie an undiscovered tenth planet two to
five times the size of Earth. Astronomers at the U.S.
Naval Observatory (USNO) are using a powerful
computer to identify the best target zones, and a
telescopic search will follow soon after. ... Van Flandern
thinks the tenth planet may have between two and five
Earth masses and lie 50 to 100 astronomical units from
the Sun. (An astronomical unit is the mean distance
between Earth and the Sun.) His team also presumes
that, like Pluto's, the plane of the undiscovered body's
orbit is tilted with respect to that of most other planets,
and that its path around the Sun is highly elliptical.
In Article <dkZK6.5183$n81.2...@typhoon.hawaii.rr.com> David Tholen
wrote:
> Magnification is simply the ratio of the focal lengths of the
> primary and the eyepiece. Simply changing the eyepiece to
> one with a different focal length can change the magnification.
> There are more amateur telescopes designed to change eyepieces
> than "observatory scopes". The latter rarely have eyepieces
> nowadays. They hang a CCD camera at the focus and get whatever
> image scale corresponds to the focal length for that focus.
If we're dealing with a sighting of an object AS SMALL as Pluto in the
sights, at present, then what kind of equipment is required, by amateurs
to view Pluto as other than a pin-point of dimly reflected sunlight?
Bob May
moon! It's all simple math which I won't bother to involve you with as you
are probably as math stupid as you are otherwise. It's simple geometry if
you can handle it. I might also note to you that I have personally seen
Pluto in a 10" scope which is now a common size for a scope in the hands of
amateurs and scopes twice the size in diameter are becoming the standard
size for many people. Scopes that big make finding Pluto a real easy job.
Things like the Einstein Cross are becoming regular targets for visual
observation due to their dimness which is a lot less than what you are
specifying for your planet x.
--
Bob May
Remember that computers do exactly what you tell them to do, not what you
think you told them to do.
da...@pebble.org
> Sigh, Pluto has been imaged as a disk, dummy! That's how they found the
> moon!
Bob, I was under the impression that the disk of Pluto has never been
_directly_ imaged, but rather was slowly mapped over time by measuring
brightness changes during the many mutual occultations of Pluto and
Charon that occured some years back now.
- Dan
Martin Brown
da...@pebble.org wrote:
That was how it was originally detected in the late 70's, but the HST can
actually image Pluto's disk directly. Not so many pixels across it, but
definitely resolved as a disk. See eg.
http://www.seds.org/hst/PlutoCharon.html
Regards,
Martin Brown
Brian Tung
> > Sigh, Pluto has been imaged as a disk, dummy! That's how they found the
> > moon!
>
> Bob, I was under the impression that the disk of Pluto has never been
> _directly_ imaged, but rather was slowly mapped over time by measuring
> brightness changes during the many mutual occultations of Pluto and
> Charon that occured some years back now.
The occultation work was done, if I recall correctly, by none other than
Dave Tholen and Marc Buie, among others. The best *ground*-based images
have done little more than to show a bigger blob for Pluto than the one
for Charon, and even then it's unclear to my untrained eyes whether that
is really because Pluto is larger, or only because it's also brighter.
However, the Hubble Space Telescope, which is based in space, *has* shown
a disc for Pluto at least, and I think also for Charon.
Brian Tung <br...@isi.edu>
Astronomy Corner at http://astro.isi.edu/
C5+ Home Page at http://astro.isi.edu/c5plus/
PalmAtlas Home at http://astro.isi.edu/palmatlas/
tho...@antispam.ham
>> Pluto is only 0.1 arcsec in diameter, so something
>> smaller than Pluto will be smaller than 0.1 arcsec.
>> You'd need something like a 40-inch telescope to
>> have a diffraction limit less than 0.1 arcsec at visible
>> wavelengths, and you'd still have atmosphere seeing
>> as the limiting factor.
> Do observatories view Pluto?
How do you think it was discovered?
> I assume yes.
No need to assume it.
> What do they see?
Something starlike, not diffuse.
> If so, then they can view Planet X.
Not as a diffuse object.
> Pluto is reflecting sunlight, Planet X does not but has its own
> diffuse glow.
Then it can't be smaller than Pluto. Why do you persist with such an
obvious contradiction?
> I quote from my rediculously outdated and silly book, The Solar System,
> a Practical Guide (insulted ahead of time to save David Tholen time):
If you really wanted to save me time, you wouldn't post at all.
> .. 1978 when Pluto's moon was found. Work on the
> orbit of Pluto had been continuing at the United States
> Naval Observatory since 1930 in an effort to refine still
> further the pertubations in the orbits of Uranus and
> Neptune and to find, if possible, a tenth planet from its
> effect on the orbits of the outer planets. To this end, a
> set of high-resolution plates of Pluto were made using
> the USNO's 155 cm reflecting telescope at Flagstaff
> over three nights in April and May 1978. ... The image
> of Pluto had a bulge. ... With confirming observatorions
> being made with the 3 m Cerro Tololo telescope,
There is no 3-m Cerro Tololo telescope.
> Harrington calculated that the moon had a period of 6
> days 9 hours and was 20,000 km from the surface of Pluto
> ... Pluto was found to have a mass of .0002 Earths.
>
> The Zetas have stated that Planet X has 23 times the mass, and is 4
> times the diameter of Earth while at 18.74 Sun-Pluto distance.
Do the math. Compute the angular diameter of such an object. Not
"diffuse". Not even resolvable in most telescopes due to atmospheric
seeing.
> Van Flandern, during the search for Planet X in the early 1980's,
> stated he computed it to be up to 5 times the size of Earth while
> at 50-100 AU to account for the perturbations in the outer planets.
> I quote:
>
> Astronomy, Dec 1981
> Search for the Tenth Planet
>
> Astronomers are readying telescopes to probe the outer
> reaches of our solar system for an elusive planet much
> larger than Earth. Its existence would explain a
> 160-year-old mystery.
The mystery was solved by Standish in a more recent paper. Odd that
you like to reference only those papers that support your notions,
not the ones that destroy it.
> ... The pull exerted by its gravity
> would account for a wobble in Uranus' orbit that was
> first detected in 1821 by a French astronomer, Alexis
> Bouvard.
There is no "wobble in Uranus' orbit". The residuals were due to
errors in the star catalogs used at the time, plus an incorrect
mass for Neptune when computing its perturbation on Uranus.
>> Magnification is simply the ratio of the focal lengths of the
>> primary and the eyepiece. Simply changing the eyepiece to
>> one with a different focal length can change the magnification.
>> There are more amateur telescopes designed to change eyepieces
>> than "observatory scopes". The latter rarely have eyepieces
>> nowadays. They hang a CCD camera at the focus and get whatever
>> image scale corresponds to the focal length for that focus.
> If we're dealing with a sighting of an object AS SMALL as Pluto in the
> sights, at present, then what kind of equipment is required, by amateurs
> to view Pluto as other than a pin-point of dimly reflected sunlight?
The key word here is "if". What we're really dealing with is your
skewed notion that observatory "scopes" "zoom".
Amateurs cannot view Pluto as anything other than a pinpoint as long
as they're looking through the Earth's turbulent atmosphere. Maybe
at some time in the distant future, amateurs might have an 80-inch
telescope with adaptive optics or located on the Moon. Until that
time, Pluto will remain a pinpoint when they look at it.
tho...@antispam.ham
> Sigh, Pluto has been imaged as a disk, dummy!
True, but it took the HST Faint Object Camera to do it. Surface models
were derived from fits to mutual event photometry, but it's a stretch
to call that approach "imaging".
> That's how they found the moon!
No. The moon was found by examining photographs taken under
conditions of better than average seeing. Pluto was NOT imaged
as a disk at the time.
> It's all simple math which I won't bother to involve you with as you
> are probably as math stupid as you are otherwise. It's simple geometry if
> you can handle it.
Apparently not as simple as you thought.
tho...@antispam.ham
> Bob May wrote:
>> Sigh, Pluto has been imaged as a disk, dummy! That's how they found the
>> moon!
> Bob, I was under the impression that the disk of Pluto has never been
> _directly_ imaged,
That's an incorrect impression. HST's Faint Object Camera got something
like 7 pixels across the disk of Pluto.
> but rather was slowly mapped over time by measuring brightness changes
> during the many mutual occultations of Pluto and Charon that occured
> some years back now.
That effort predates the direct imaging by HST. Also, due to the tidal
lock, the mutual events were able to map only a single hemisphere of
Pluto, whereas the HST images are global, save for a small patch around
the south pole.
tho...@antispam.ham
> da...@pebble.org wrote:
>> Bob May wrote:
>>> Sigh, Pluto has been imaged as a disk, dummy! That's how they found the
>>> moon!
>> Bob, I was under the impression that the disk of Pluto has never been
>> _directly_ imaged, but rather was slowly mapped over time by measuring
>> brightness changes during the many mutual occultations of Pluto and
>> Charon that occured some years back now.
> That was how it was originally detected in the late 70's,
Actually, the mutual events occurred from 1985 to 1990. The discovery
of Charon was in 1978, but no mapping during mutual events occurred in
the late 70s.
tho...@antispam.ham
> Dan wrote:
>>> Sigh, Pluto has been imaged as a disk, dummy! That's how they found the
>>> moon!
>> Bob, I was under the impression that the disk of Pluto has never been
>> _directly_ imaged, but rather was slowly mapped over time by measuring
>> brightness changes during the many mutual occultations of Pluto and
>> Charon that occured some years back now.
> The occultation work was done, if I recall correctly, by none other than
> Dave Tholen and Marc Buie, among others.
Including Rick Binzel, Eliot Young, and Vadim Burwitz, to name the
other principal players.
> The best *ground*-based images
> have done little more than to show a bigger blob for Pluto than the one
> for Charon, and even then it's unclear to my untrained eyes whether that
> is really because Pluto is larger, or only because it's also brighter.
Hot off the presses: I have new images from last month using adaptive
optics on Gemini North. The best of the bunch has FWHM < 0.09 arcsec,
which is actually smaller than the disk of Pluto. Not that I expect to
see any surface features. The goal of the observations is to confirm
the orbital eccentricity for Charon.
> However, the Hubble Space Telescope, which is based in space, *has* shown
> a disc for Pluto at least, and I think also for Charon.
About 3 pixels for Charon, as I recall.
Gar...@truss.net
Hubble imaged it.
Now for yet ANOTHER ........*PLONK!*
tho...@antispam.ham
> Now for yet ANOTHER ........*PLONK!*
Why waste the bandwidth to tell us that?
JJ
exposure time in order to get the below referenced image?
http://www.seds.org/hst/PlutoCharon.html
And the same question for this one (or at least the little ones in the
upper left corners)?
http://ftp.seds.org/pub/images/hst/Pluto4.jpg
Much obliged,
JJ
"Martin Brown" <martin...@pandora.be> wrote in message
news:3B02DC07...@pandora.be...
Martin Brown
JJ wrote:
> Does anyone know or can someone point me to a link that would show the
> exposure time in order to get the below referenced image?
>
> http://www.seds.org/hst/PlutoCharon.html
I think around 10-25 mins on a series of exposures. Complete details from ADS
at:
(warning seriously big file)
Regards,
Martin Brown
JJ
You were spot on. The exposures show the shortest time to be about 6
minutes and the longest to be about 28 minutes.
PDF file size = 2,454 kilobytes. Well worth every second waiting for it
to download!
A quick pass over the article and its images indicates to me that even
HST's Faint Object Camera didn't have an easy time with Pluto. I guess my
little 8" reflector is going to need a lot more than just clear air and a
steady tripod to see this planet.
Thanks again,
JJ
"Martin Brown" <martin...@pandora.be> wrote in message
news:3B038477...@pandora.be...
Brian Tung
> I think around 10-25 mins on a series of exposures. Complete details from
> ADS at:
>
> http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?
> bibcode=1997AJ....113..827S&data_type=PDF_HIGH&type=PRINTER
[join lines --brian]
Thanks, Martin.
For anyone who is sufficiently familiar with the process: Near the
beginning of Section 4.1, the authors state that, "To remove the PSF,
we solved for the image that, when convolved with the PSF, would best
match the observed image. This technique is superior to image
convolution because it is less sensitive to subtleties of the actual
PSF."
Can someone explain to me what the difference between the two processes
is? I know what convolution is (at least, in my own work I do--perhaps
it means something different here), and the two sound very similar to
me.
For example, if we call the raw image R and the PSF P, then the first
option sounds like solving for the input image I such that
I * P = R
where * is the convolution. Whereas the second one sounds like starting
by computing the inverse of P, P^(-1), and then computing I directly:
I = R * P^(-1)
(I seem to recall doing this on a dummy image: I made an image I, made
up a PSF P, and computed R = I * P. Then I computed P^(-1), and recovered
I by computing I = R * P^(-1).)
It sounds like I must have one (or both) of these wrong. Can someone
help?
John Shakespeare
Brian Tung wrote:
I'm not sure you have it wrong at all. But if you were able to do this with
simple inversions, then the test P that you used may not have been realistic.
In practical cases, the PSF does not have an inverse, unless you down-sample to
a much lower resolution. Think in Fourier space for the 1 dimensional case:
r(x)=i(x)*p(x)
R(jw)=I(jw)P(jw)
Superficially, it seems we can recover i(x) through I(jw) by a simple
inversion:
I(jw)=R(jw)/P(jw)
However, the PSF in practical cases has zeros at high frequencies, so this
inversion is possible only if the Nyquist frequency of the image is lower than
the lowest zero in P(jw). Actually, there is some uncertainty in P(jw), so we
must cut off at the highest frequency for which P(jw) can be _reliably_
inverted (choose your desired S/N ratio for the "reliable" criterion).
In general, deconvolution methods attempt to find i(x) or I(jw) which is is
both consistent with r(x) and p(x), and which is _plausible_ in the particular
physical context of the problem. Obviously, if we find some i(x) which is
consistent with r(x) and p(x), then we can find any number of others, by adding
functions k(x) whose spectral content is entirely within the zeros of P(jw),
such that K(jw)P(jw)=0. Plausibility of k(x) in a particular situation may be
subjective, and each algorithm may be accepted only for a particular class of
problems.
Note that the approach of deconvoluting through convolution is effectively
taking the inverse of P(jw) at those frequencies for which an inverse exists,
and zeroing the others. In other words, it uses I(jw)=R(jw)Q(jw), where
Q(jw)=1/P(jw) if |P(jw)|>deadband, and Q(jw)=0 otherwise. Therein lies the
difference, there is no K(jw) in this class of methods.
There is an extensive literature on deconvolution, as it pops up in so many
physical situations, especially in measurement. The methods have been in use in
spectroscopy for several decades, and were adopted more recently in image
processing. A couple of simple algorithms for images are used in "Handbook of
Astronomical Image Processing" by R. Berry & J. Burnell. A more comprehensive
reference is "Deconvolution of Images and Spectra" by P. Jansson.
Best Regards,
John.
Brian Tung
> I'm not sure you have it wrong at all. But if you were able to do this
> with simple inversions, then the test P that you used may not have been
> realistic.
>
Thanks, John; I think I get it now. I'll go off and think about it some
more, but what you wrote certainly helps.
Magnus Nyborg
"John Shakespeare" <john.sha...@tut.fi> wrote in message
news:3B043182...@tut.fi...
[some very good stuff]
It is interesting to note that if one deconvolves using the factual PSF,
then the sampling-criterion will be violated. For best results, one should
deconvolve an image I convolved with PSF P using a 'smaller' PSF P' such
that P' * R = P and where R is some small distribution (fex Gaussian with
FWHM = 2.0 - i.e. to deconvolve the PSF before deconvolving the image).
There is an interesting article on this subject and more at
http://www.jobpilot.se/stellenanzeigen/7d1/d/509902.htm
Clear Skies,
Magnus
John Shakespeare
Magnus Nyborg wrote:
> "John Shakespeare" <john.sha...@tut.fi> wrote in message
> news:3B043182...@tut.fi...
> [some very good stuff]
>
> It is interesting to note that if one deconvolves using the factual PSF,
> then the sampling-criterion will be violated. For best results, one should
> deconvolve an image I convolved with PSF P using a 'smaller' PSF P' such
> that P' * R = P and where R is some small distribution (fex Gaussian with
> FWHM = 2.0 - i.e. to deconvolve the PSF before deconvolving the image).
Yes, there are many little wrinkles in deconvolution. It is, after all, a rank
deficient problem.
> There is an interesting article on this subject and more at
> http://www.jobpilot.se/stellenanzeigen/7d1/d/509902.htm
>
This link appears to be an advertisement for a position in Italy!!! Are you
looking for warmer climes, perchance?
Best Regards,
John.
Magnus Nyborg
> Hi Magnus,
[...]
> This link appears to be an advertisement for a position in Italy!!! Are
you
> looking for warmer climes, perchance?
Sorry, copy-paste incorrectly. My girlfriend is and lives in Rome...
Here's the correct link
http://vela.astro.ulg.ac.be/themes/dataproc/deconv/articles/deconv/deconv.ht
ml
Clear Skies,
Magnus
>
> Best Regards,
> John.
>
David W Knisely
> A quick pass over the article and its images indicates to me that even
> HST's Faint Object Camera didn't have an easy time with Pluto. I guess my
> little 8" reflector is going to need a lot more than just clear air and a
> steady tripod to see this planet.
>
Well, under good seeing conditions and under a fairly dark sky, Pluto
can be seen in a scope smaller than 8 inches. I have seen it (barely)
using only a 3.7 inch aperture, although it is easier with larger
scopes. The key is to use enough power (10x to 15x per inch of
aperture) to get the scale up a little and dilute the faint background
skyglow. Its current visual magnitude is about 13.8, but don't let that
discourage you from trying to find it. It takes a good star atlas to
identify the field stars (I use a printed Megastar chart nearly a degree
wide centered on Pluto's position with stars plotted down to magnitude
14.5) and some patience (as well as proper dark adaptation and averted
vision), but it can be done. Good hunting and clear skies to you.
--
David Knisely KA0...@navix.net
Prairie Astronomy Club, Inc. http://www.4w.com/pac
Hyde Memorial Observatory:
http://www.blackstarpress.com/arin/hyde
***********************************************
* Attend the 8th Annual NEBRASKA STAR PARTY *
* July 14-20, 2001 http://www.4w.com/nsp *
***********************************************
tho...@antispam.ham
> Well, under good seeing conditions and under a fairly dark sky, Pluto
> can be seen in a scope smaller than 8 inches. I have seen it (barely)
> using only a 3.7 inch aperture,
Which means you should be able to see magnitude 8 stars with a dark
adapted naked eye.
Magnus Nyborg
<tho...@AntiSpam.ham> wrote in message
news:Jl9N6.3005$WI.4...@typhoon.hawaii.rr.com...
Don't leave out the detection-enhancing effects of using a high
magnification !
Although detecting a mag 8 object with the unaided eye may be extremely
difficult, detecting it under similar circumstances with a higher
magnification can be much easier...
Clear Skies,
Magnus
Nancy Lieder
MAGNIFIED by observatories. And it appears as a "blob" (i.e. DIFFUSE,
not a pin-point) to some. Thanks guys. Planet X, being larger but
farther out, likewise needs to be magnified at an observatory, and to
those who sighted it, the "blob" description applied, as I recall.
In Article <3B02DC07...@pandora.be> Martin Brown wrote:
> That was how it was originally detected in the late 70's,
> but the HST can actually image Pluto's disk directly. Not
> so many pixels across it, but definitely resolved as a disk.
> See eg.
> http://www.seds.org/hst/PlutoCharon.html
In Article <9duqfi$klc$1...@zot.isi.edu> Brian Tung wrote:
> The occultation work was done, if I recall correctly,
> by none other than Dave Tholen and Marc Buie, among
> others. The best *ground*-based images have done
> little more than to show a bigger blob for Pluto than the
> one for Charon, and even then it's unclear to my
> untrained eyes whether that is really because Pluto is
> larger, or only because it's also brighter.
>
> However, the Hubble Space Telescope, which is based
> in space, *has* shown a disc for Pluto at least, and I
> think also for Charon.
In Article <ABCM6.7397$n81.2...@typhoon.hawaii.rr.com> David Tholen
wrote:
> That effort predates the direct imaging by HST. Also,
> due to the tidal lock, the mutual events were able to
> map only a single hemisphere of Pluto, whereas the
> HST images are global, save for a small patch around
> the south pole. ... HST's Faint Object Camera got
Nancy Lieder
> Well, under good seeing conditions and under a
> fairly dark sky, Pluto can be seen in a scope smaller
> than 8 inches. I have seen it (barely) using only a 3.7
> The key is to use enough power (10x to 15x per inch of
> aperture) to get the scale up a little and dilute the faint
> background skyglow. Its current visual magnitude is
> about 13.8
For Planet X, filter FOR red to screen out .. whatever (as in background
skyglow for David's Pluto sighting). Expect a "visual magnitude" of 11,
due to its distance from Earth. Good conditions (David's "good seeing
conditions under a fairly dark sky") helps, of course (the Russian
attempt in February and a recent attempt in Australia was blocked by
cloud cover or poor sky conditions). Go to an observatory that will
magnify like crazy, so you can catch sight of this dim bulb (the "enough
power" and "scale up" in David's description.
June coordinates will likewise be posted, so make your reservations!
ALL those observatories can't have piping in front of the scopes when
they are pointed toward Orion/Taurus or be closed for the season,
suddenly, as in Vancouver! Who's going to be the first to provide a
REAL image of this smoldering inbound brown dwarf, which will NOT move
along a path according to the ephemeris, nor will it be stationary in
the sky as it is on the move, inbound! You might even get to name it!
Bob's Blob or David's Dim-n-Diffuse or Zack's Planet Z or whatever.
Nancy Lieder
> The exposures show the shortest time to be about 6
> A quick pass over the article and its images indicates
> have an easy time with Pluto. I guess my little 8"
> reflector is going to need a lot more than just clear
> air and a steady tripod to see this planet.
Well that explains why an image is not so easy to come by. Neuchatal
folks (who did not get offical permission to release the information)
got an image, but this was never received, though the descriptions of
what was sighted at the coordinates given by the Zetas were consistent.
We were told that by the excited folks who first sighted it that we
would get "at least" an image, then were was a long silence for over a
week, then the offical denial that such as sighting ever occurred at
Neuchatal. So they've got an immage.
> Subject: 12th planet discovery?
> Date: Wed, 07 Feb 2001 23:30:32 +0100
>
> It seems incredible but somebody on [mailing list]
> (57 members today :-) - actually a whole team is
> contacting all and every observatories in France -
> just sent a message. The Neuchatel observatory got it.
> They are very excited, wondering if it is a comet or a
> brown dwarf, through the latest coordinates you gave.
> I'm going to ask for further details. The daughter of
> the astronomer reports that they suspect a comet or
> a brown dwarf on the process to become a pulsar
> since it emits "waves".
>
> PS for those who would read french I copy the message below
>
> Salut! Bon les jeunes y'a du nouveau. j'ai envoye
> les donnees concernant la 12e planete a une amie, et
> voici ce qu'elle me repond: Observatoire de Neuchâtel
> (celui du paternel) toute première réponses: oui,ce
> pourrait être une comète. Elle est sur un des bras
> d'Orion(?) et vont se mettre à mieux regarder pour
> valider ou non "la naine brune"...car je ne sais pas
> si tu sais, mais ce stade est juste avant celui du pulsar
> et donc émet des ondes... CQFD... je me demande ce
> que la Terre en reçoit ou en recevra mais... Mystère
> et boules de gommes... Attendons les autres labo...
> mais celui-ci en particulier je lui fait confiance car
> il ne jouerait pas la carte du complot avec mon père...
> ça franchement non... (autant dire que le - dit Père
> est tout exité!!!)
tho...@antispam.ham
>> David W Knisely writes:
>>> Well, under good seeing conditions and under a fairly dark sky, Pluto
>>> can be seen in a scope smaller than 8 inches. I have seen it (barely)
>>> using only a 3.7 inch aperture,
>> Which means you should be able to see magnitude 8 stars with a dark
>> adapted naked eye.
> Don't leave out the detection-enhancing effects of using a high
> magnification !
Magnify too much and you spread out the photons over too large an
area.
> Although detecting a mag 8 object with the unaided eye may be extremely
> difficult, detecting it under similar circumstances with a higher
> magnification can be much easier...
Magnification involves some optics, and those optics could be
gathering more light than the eye alone could do.
Brian Tung
> > Don't leave out the detection-enhancing effects of using a high
> > magnification !
>
> Magnify too much and you spread out the photons over too large an
> area.
True. However, empirically, I can see more with a 7x5 pair of binoculars
(masked down to 5 mm as carefully as I could manage) than I can with the
unaided eye. So I submit that perhaps David Knisely's feat doesn't mean
that he could see magnitude 8 stars with the unaided eye--although it
does seem to mean that he could see them with a 5 mm objective (or whatever
his pupil size was) and some degree of magnification.
I will admit that *finding* things with a pair of 7x5 binoculars is a
difficult feat. I needed a tripod to steady the view. (I used the area
around alpha Persei, if you're curious.)
tho...@antispam.ham
> Neuchatal folks (who did not get offical permission to release the
> information) got an image, but this was never received,
How convenient for you. Interesting that you haven't accused them
of cover-up the way you've accused NASA for HST images that were
allegedly never released.
> though the descriptions of what was sighted at the coordinates
> given by the Zetas were consistent.
Impossible, given that your own descriptions have been inconsistent.
> We were told that by the excited folks who first sighted it that we
> would get "at least" an image, then were was a long silence for over a
> week, then the offical denial that such as sighting ever occurred at
> Neuchatal.
Was the original claim of a sighting "official"?
> So they've got an immage.
On what basis do you make that claim? You just finished telling us
about an official denial that such a sighting ever occurred there.
tho...@antispam.ham
> For Planet X, filter FOR red to screen out .. whatever (as in background
> skyglow for David's Pluto sighting). Expect a "visual magnitude" of 11,
> due to its distance from Earth.
I see that you still haven't addressed the matter of thermal equilibrium.
Exactly how do you propose to get an object with a "visual magnitude" of
11 that doesn't reflect any light?
> Go to an observatory that will magnify like crazy,
What good would that do? It would make your diffuse object even more
diffuse and therefore harder to detect.
> June coordinates will likewise be posted, so make your reservations!
While it's in conjunction with the Sun.
> ALL those observatories can't have piping in front of the scopes when
> they are pointed toward Orion/Taurus or be closed for the season,
> suddenly, as in Vancouver!
They can all have it in conjunction with the Sun.
> Who's going to be the first to provide a REAL image of this smoldering
> inbound brown dwarf,
Nobody, because the object isn't real.
> which will NOT move along a path according to the ephemeris,
You've provided an ephemeris. Are you now claiming that it won't
follow your own ephemeris?
> nor will it be stationary in the sky as it is on the move, inbound!
Then it would supposedly follow a path that you could tabulate in an
ephemeris. Yet another contradiction.
tho...@antispam.ham
> OK, so Pluto can be seen, as something other than a pin-point, as it is
> MAGNIFIED by observatories.
Actually, only HST has ever imaged it as something other than a pin-point,
and that's because of the lack of atmospheric turbulence, coupled with a
long focal length, giving an image scale that allowed several pixels
across the disk.
> And it appears as a "blob" (i.e. DIFFUSE, not a pin-point) to some.
Actually, it appears as just as much a "blob" as any other star suffering
from atmospheric turbulence. The seeing is a function of the atmosphere,
not the telescope.
> Planet X, being larger but farther out,
Previously you claimed that it's smaller than Pluto. Now it's larger.
You're self-contradictory, Nancy.
tho...@antispam.ham
>>> Don't leave out the detection-enhancing effects of using a high
>>> magnification !
>> Magnify too much and you spread out the photons over too large an
>> area.
> True. However, empirically, I can see more with a 7x5 pair of binoculars
> (masked down to 5 mm as carefully as I could manage) than I can with the
> unaided eye.
Do such a pair of binoculars actually exist? And why would you need to
mask a 5 mm aperture "down" to 5 mm?
> So I submit that perhaps David Knisely's feat doesn't mean
> that he could see magnitude 8 stars with the unaided eye--although it
> does seem to mean that he could see them with a 5 mm objective (or whatever
> his pupil size was) and some degree of magnification.
Magnification involves some optics, which could gather more light than
the naked eye.
> I will admit that *finding* things with a pair of 7x5 binoculars is a
> difficult feat.
Just finding a pair of 7x5 binoculars seems like a difficult feat.
Brian Tung
> Do such a pair of binoculars actually exist? And why would you need to
> mask a 5 mm aperture "down" to 5 mm?
Sorry, I was confusing. I had a pair of 7x35 binoculars. I made a mask
to cover both objectives down to 5 mm each.
(I don't have the 7x35 binoculars anymore. Nor the mask, for that
matter.)
> Magnification involves some optics, which could gather more light than
> the naked eye.
I don't see how either objective, when masked, could have gathered more
than the 5 mm of light that the corresponding alone would have been able
to gather. Can you explain?
tho...@antispam.ham
>> Do such a pair of binoculars actually exist? And why would you need to
>> mask a 5 mm aperture "down" to 5 mm?
> Sorry, I was confusing. I had a pair of 7x35 binoculars. I made a mask
> to cover both objectives down to 5 mm each.
>
> (I don't have the 7x35 binoculars anymore. Nor the mask, for that
> matter.)
>> Magnification involves some optics, which could gather more light than
>> the naked eye.
> I don't see how either objective, when masked, could have gathered more
> than the 5 mm of light that the corresponding alone would have been able
> to gather. Can you explain?
The question is whether it gathers more light than the human eye.
Anti-reflection coatings can affect the amount of light that a
5 mm lens can transmit, and the way in which that light enters the
human eye could affect how much gets to the retina.
Brian Tung
> > I don't see how either objective, when masked, could have gathered more
> > than the 5 mm of light that the corresponding alone would have been able
> > to gather. Can you explain?
>
> The question is whether it gathers more light than the human eye.
> Anti-reflection coatings can affect the amount of light that a
> 5 mm lens can transmit, and the way in which that light enters the
> human eye could affect how much gets to the retina.
My mistake again. Between "corresponding" and "alone," please insert
"eye." I meant to put that in there, and forgot.
David W Knisely
That is quite correct. Under dark sky conditions from prime observing
locations, the unaided human eye has occasionally allowed the viewing of
stars down to 8th magnitude. In fact, a few observers have gone even
fainter. In 1995, Nevada amateur Dave Nash did a limiting magnitude
test at the site of the Nebraska Star Party (Merritt Reservoir, 3100 ft
elevation), noting the stars he could see in a limited area of sky high
overhead. He communicated which stars he had seen to Brian Skiff of
Lowell Observatory, and Brian identified one which Dave had seen which
was magnitude 8.2! Many star party attendees have gone nearly as faint
from that site, and there are probably at least a few other sites in the
U.S. where skilled observers can duplicate this feat. As for the
challenge of seeing Pluto, there are reports of it being seen from
higher alitudes (over 4000 ft elevation) with apertures in the 70mm to
90mm range. I first saw Pluto in an 8 inch in the mid 1970's after I
had learned to kick up the power slightly to make it stand out somewhat
better. This technique has served me well for viewing things like
fainter detail in some smaller spiral galaxies. I often use powers from
about 10x per inch to 15x per inch of aperture on galaxies and have
found the additional magnification to be quite beneficial in revealing
some additional detail. There are some galaxies which will stand even
more power (220x to 253x with my ten inch Newtonian), so the tired old
adage of staying with "low power" to view galaxies isn't entirely
accurate under all conditions. Very high power is also necessary for
some faint observing challenges such as the viewing of the central star
in the Ring Nebula (M57). The star can sometimes be observed in
apertures as small as ten inches using very high powers (over 300x) if
the seeing conditions are *very* stable and the sky is quite dark and
clear. When trying for the star with my ten inch, I *start* at 353x and
go up from there. Pluto currently doesn't quite require such extreme
powers, but it does help to locate the field at low power and then kick
things up a bit to see the planet itself.
Magnus Nyborg
<tho...@AntiSpam.ham> wrote in message
news:dlhN6.3074$WI.5...@typhoon.hawaii.rr.com...
> Magnus Nyborg writes:
>
> >> David W Knisely writes:
>
> >>> Well, under good seeing conditions and under a fairly dark sky, Pluto
> >>> can be seen in a scope smaller than 8 inches. I have seen it (barely)
> >>> using only a 3.7 inch aperture,
>
> >> Which means you should be able to see magnitude 8 stars with a dark
> >> adapted naked eye.
>
> > Don't leave out the detection-enhancing effects of using a high
> > magnification !
>
> Magnify too much and you spread out the photons over too large an
> area.
I didn't say magnify too much...
>
> > Although detecting a mag 8 object with the unaided eye may be extremely
> > difficult, detecting it under similar circumstances with a higher
> > magnification can be much easier...
>
> Magnification involves some optics, and those optics could be
> gathering more light than the eye alone could do.
Yes, it can. But if you base a formula of how dim objects that can be
detected on what you can see with the unaided eye, then you are up for a big
surpirse. It doesn't work !
So if the unaided can barely detect a mag 7.0 object on a given night, a
telescope might still allow detection of something like mag 8.0 +
5.0*log(D/7.0), if a proper magnification is choosen...or sometimes even
better...
Clear Skies,
Magnus
>
tho...@antispam.ham
>>> I don't see how either objective, when masked, could have gathered more
>>> than the 5 mm of light that the corresponding alone would have been able
>>> to gather. Can you explain?
>> The question is whether it gathers more light than the human eye.
>> Anti-reflection coatings can affect the amount of light that a
>> 5 mm lens can transmit, and the way in which that light enters the
>> human eye could affect how much gets to the retina.
> My mistake again. Between "corresponding" and "alone," please insert
> "eye." I meant to put that in there, and forgot.
That doesn't really answer my question. A 5 mm lens isn't necessarily
going to gather the same amount of light as a 5 mm eye pupil. There
are losses at the surfaces, and the degree of loss could presumably
be a function of how the light approaches the surface (smooth glass
reflects about 4 percent at normal incidence, but considerably more
at grazing incidence, for example). The optics in front of the eye
are going to change how the light approaches the surface.
tho...@antispam.ham
> RE: Pluto visual observations, Tholen posted:
Gee, I'm not some "sad person" or "sad and bitter person" or "Tholen
person" this time?
>>> Well, under good seeing conditions and under a fairly dark sky, Pluto
>>> can be seen in a scope smaller than 8 inches. I have seen it (barely)
>>> using only a 3.7 inch aperture,
>> Which means you should be able to see magnitude 8 stars with a dark
>> adapted naked eye.
> That is quite correct. Under dark sky conditions from prime observing
> locations, the unaided human eye has occasionally allowed the viewing of
> stars down to 8th magnitude. In fact, a few observers have gone even
> fainter. In 1995, Nevada amateur Dave Nash did a limiting magnitude
> test at the site of the Nebraska Star Party (Merritt Reservoir, 3100 ft
> elevation), noting the stars he could see in a limited area of sky high
> overhead. He communicated which stars he had seen to Brian Skiff of
> Lowell Observatory, and Brian identified one which Dave had seen which
> was magnitude 8.2! Many star party attendees have gone nearly as faint
> from that site, and there are probably at least a few other sites in the
> U.S. where skilled observers can duplicate this feat. As for the
> challenge of seeing Pluto, there are reports of it being seen from
> higher alitudes (over 4000 ft elevation) with apertures in the 70mm to
> 90mm range.
At the lower end of that range, you're now talking about the ability to
see magnitude 8.7 with the naked eye.
> I first saw Pluto in an 8 inch in the mid 1970's after I
> had learned to kick up the power slightly to make it stand out somewhat
> better.
How can you be sure that you really saw it as opposed to having imagined
that you saw it?
> This technique has served me well for viewing things like
> fainter detail in some smaller spiral galaxies. I often use powers from
> about 10x per inch to 15x per inch of aperture on galaxies and have
> found the additional magnification to be quite beneficial in revealing
> some additional detail. There are some galaxies which will stand even
> more power (220x to 253x with my ten inch Newtonian), so the tired old
> adage of staying with "low power" to view galaxies isn't entirely
> accurate under all conditions.
Point sources are not the same as extended objects.
tho...@antispam.ham
>>>> David W Knisely writes:
>>>>> Well, under good seeing conditions and under a fairly dark sky, Pluto
>>>>> can be seen in a scope smaller than 8 inches. I have seen it (barely)
>>>>> using only a 3.7 inch aperture,
>>>> Which means you should be able to see magnitude 8 stars with a dark
>>>> adapted naked eye.
>>> Don't leave out the detection-enhancing effects of using a high
>>> magnification !
>> Magnify too much and you spread out the photons over too large an
>> area.
> I didn't say magnify too much...
Any kind of magnification spreads out the photons.
>>> Although detecting a mag 8 object with the unaided eye may be extremely
>>> difficult, detecting it under similar circumstances with a higher
>>> magnification can be much easier...
>> Magnification involves some optics, and those optics could be
>> gathering more light than the eye alone could do.
> Yes, it can. But if you base a formula of how dim objects that can be
> detected on what you can see with the unaided eye, then you are up for a big
> surpirse. It doesn't work !
Detected with what?
> So if the unaided can barely detect a mag 7.0 object on a given night, a
> telescope might still allow detection of something like mag 8.0 +
> 5.0*log(D/7.0), if a proper magnification is choosen...or sometimes even
> better...
Can you explain that?
Brian Tung
> That doesn't really answer my question. A 5 mm lens isn't necessarily
> going to gather the same amount of light as a 5 mm eye pupil. There
> are losses at the surfaces, and the degree of loss could presumably
> be a function of how the light approaches the surface (smooth glass
> reflects about 4 percent at normal incidence, but considerably more
> at grazing incidence, for example). The optics in front of the eye
> are going to change how the light approaches the surface.
Fair enough. But we were originally talking about Knisely's sighting of
Pluto through a 3.7-inch (around 90 or 95 mm) aperture. That is about 18
or 19 times wider than that 5 mm (effective) lens. If we are to take a
formulaic approach, that should see about 6.2 magnitudes deeper than the
5 mm lens. (5 log (18 or 19)^2)
On the night in question, I could see to magnitude 6.5 (give or take maybe
0.2) with the unaided eye, to magnitude 7.5 with one eye of the masked
binocs, and to magnitude 7.8 with both eyes. (I'm talking about stars.)
That means that I should be able to see to magnitude 13.7 with the 90 to
95 mm aperture. I think Pluto's magnitude has been in that neighborhood
at least part of the year, during recent years.
At least, that's what it means to me, and I'm satisfied David could have
seen Pluto the way he did, without necessarily being able on that night to
see magnitude 8.0 stars with the unaided eye.
Brian Tung
> Fair enough. But we were originally talking about Knisely's sighting of
> Pluto through a 3.7-inch (around 90 or 95 mm) aperture. That is about 18
> or 19 times wider than that 5 mm (effective) lens. If we are to take a
> formulaic approach, that should see about 6.2 magnitudes deeper than the
> 5 mm lens. (5 log (18 or 19)^2)
Oops. That should just be 5 log (18 or 19).
Magnus Nyborg
<tho...@AntiSpam.ham> wrote in message
news:SmuN6.3423$WI.6...@typhoon.hawaii.rr.com...
> Magnus Nyborg writes:
[...]
> > I didn't say magnify too much...
>
> Any kind of magnification spreads out the photons.
First of all, this not apply for an object when it is point-like
Second, the eye does not react like a ccd-camera. Magnifying more can, as
witnessed by many, help in detecting a diffuse object.
>
> >>> Although detecting a mag 8 object with the unaided eye may be
extremely
> >>> difficult, detecting it under similar circumstances with a higher
> >>> magnification can be much easier...
>
> >> Magnification involves some optics, and those optics could be
> >> gathering more light than the eye alone could do.
>
> > Yes, it can. But if you base a formula of how dim objects that can be
> > detected on what you can see with the unaided eye, then you are up for a
big
> > surpirse. It doesn't work !
>
> Detected with what?
With the eye !
>
> > So if the unaided can barely detect a mag 7.0 object on a given night, a
> > telescope might still allow detection of something like mag 8.0 +
> > 5.0*log(D/7.0), if a proper magnification is choosen...or sometimes even
> > better...
>
> Can you explain that?
A higher magnification (esp higher than giving a 7mm exit-pupil) can improve
the image in several ways.
1. A smaller exit-pupil uses a better part of the eye's pupil, thus making
the object more distinct.
2. The eye is not a linear device, and a larger magnification will some
times (many times) improve the contrast against the background. A linear
device can not do this.
3. The eye does not use single-pixel detection, and the eye uses some very
sofisticated imageprocessing software, implemented in a neural net.
Not having a scientificly explained model for the eye, this can not be
proven with mathematics, but clearly the eye can be proven to _not_ be
linear using a very simple test.
Detection of faint objects can easily be shown to be improved when using
higher magnificatiosn. Just try to located an object close to the limits of
the telescope using
1. 5 exit-pupil, and...
2. 1 mm exit-pupil
...and compare the results.
Pluto is fex simple in my telescope (12") at around 260x on a dark night,
but impossible at 78x (perhaps not impossible, but I have not succeded
yet)...
Clear Skies,
Magnus
>
Magnus Nyborg
<tho...@AntiSpam.ham> wrote in message
news:SmuN6.3423$WI.6...@typhoon.hawaii.rr.com...
[...]
> > I didn't say magnify too much...
>
> Any kind of magnification spreads out the photons.
First of all that is incorrect - a point-like source will not be spread out
by magnification as long as the object remains pointlike.
Secondly, you are refering to a linear device like a ccd-camera, not to the
eye...
>
> >>> Although detecting a mag 8 object with the unaided eye may be
extremely
> >>> difficult, detecting it under similar circumstances with a higher
> >>> magnification can be much easier...
>
> >> Magnification involves some optics, and those optics could be
> >> gathering more light than the eye alone could do.
>
> > Yes, it can. But if you base a formula of how dim objects that can be
> > detected on what you can see with the unaided eye, then you are up for a
big
> > surpirse. It doesn't work !
>
> Detected with what?
The eye !
>
> > So if the unaided can barely detect a mag 7.0 object on a given night, a
> > telescope might still allow detection of something like mag 8.0 +
> > 5.0*log(D/7.0), if a proper magnification is choosen...or sometimes even
> > better...
>
> Can you explain that?
Certainly:
A higher magnification (higher than giving 7mm especially) improves the
image
1. By using a better portion of the eye, and causing less aberrations inside
the eye
2. Since the eye is not linear, changing magnification can (many times do)
improve the contrast between the object and the background. A linear device
will not do this.
3. The eye does not use single-pixel detection, having a diffuse object
sometomes actually do improve detection. This is probably since the eye uses
a sophisticated imageprocessing software implemented in a neural net.
4. The darker backround at higher magnification allows the eye to darkadapt
bettter and the object will then be simpler to detect.
Certainly there are also losses in the telescope, not all light will reach
the eye when passing through an optical system. What I am arguing here is
that observations support that the gains of using higher magnifications many
times outwieghs the losses and improves the detection formula beyound what
is possible to detect with the unaided eye.
In my 12" telescope I easily detect Pluto at 260x on a dark night, but I
have yet to succeed at 78x. In fact I have detected pluto once in my 6"
telescope which according to common formulas should not be able to pick out
Pluto. Magnification was 360x when I did this, failed at lower
magnifications.
At my site, I can on a good night detect about mag 6.5 with one eye, and I
think my pupil is about 7mm when largest. My 12" telescope gathers about
1900 times more light, but only 70% reaches my eye. That gives about 1330
times brighter stars, or 7.8 mag extra detection. According to this I should
be able to detect mag 14.3, which is reasonable. Pluto is simple on a good
night. But my 6" should only be able to detect about mag 12.8, and Pluto is
always dimmer than this, yet I have managed to detect it once, and others
also report detection with even smaller instruments. A linear model simply
does not work...
Adjusting the simple formula m0 + 5.0*log( D / d) for magnification suggest
thah m0 is increasing a little as magnification goes up, perhaps as much as
1.0-1.5 mag, before the negative effects of spreading the light out becomes
to large.
Clearly, magic can not be done, but using a linear model for the eye, and
what it can detect, will fail...
Clear Skies,
Magnus
>
tho...@antispam.ham
>> That doesn't really answer my question. A 5 mm lens isn't necessarily
>> going to gather the same amount of light as a 5 mm eye pupil. There
>> are losses at the surfaces, and the degree of loss could presumably
>> be a function of how the light approaches the surface (smooth glass
>> reflects about 4 percent at normal incidence, but considerably more
>> at grazing incidence, for example). The optics in front of the eye
>> are going to change how the light approaches the surface.
> Fair enough. But we were originally talking about Knisely's sighting of
> Pluto through a 3.7-inch (around 90 or 95 mm) aperture. That is about 18
> or 19 times wider than that 5 mm (effective) lens. If we are to take a
> formulaic approach, that should see about 6.2 magnitudes deeper than the
> 5 mm lens. (5 log (18 or 19)^2)
>
> On the night in question, I could see to magnitude 6.5 (give or take maybe
> 0.2) with the unaided eye, to magnitude 7.5 with one eye of the masked
> binocs, and to magnitude 7.8 with both eyes. (I'm talking about stars.)
> That means that I should be able to see to magnitude 13.7 with the 90 to
> 95 mm aperture. I think Pluto's magnitude has been in that neighborhood
> at least part of the year, during recent years.
Only at lightcurve maximum.
> At least, that's what it means to me, and I'm satisfied David could have
> seen Pluto the way he did, without necessarily being able on that night to
> see magnitude 8.0 stars with the unaided eye.
I'm not convinced. It's very easy to imagine that you saw something very
briefly, especially when you know there is something there to be seen.
What you really need is a test involving a field where the observer does
not know what is supposed to be there.
tho...@antispam.ham
> [...]
>>> I didn't say magnify too much...
>> Any kind of magnification spreads out the photons.
> First of all, this not apply for an object when it is point-like
But everything observed through the Earth's atmosphere isn't point-like.
It's also true that even without the atmosphere, the image produced by
optics of a finite size will have a point-spread-function that will
spread out the photons with magnification. So it effectively applies
to everything.
> Second, the eye does not react like a ccd-camera. Magnifying more can,
> as witnessed by many, help in detecting a diffuse object.
First of all, I have a camcorder with a CCD in it, and it can pick up
first magnitude stars when I zoom in, but those stars will disappear
when I zoom out, so a CCD camera apparently can react like how you
believe the eye reacts. Second of all, we're talking about Pluto
here, not a diffuse object.
>>>>> Although detecting a mag 8 object with the unaided eye may be
>>>>> extremely difficult, detecting it under similar circumstances
>>>>> with a higher magnification can be much easier...
>>>> Magnification involves some optics, and those optics could be
>>>> gathering more light than the eye alone could do.
>>> Yes, it can. But if you base a formula of how dim objects that can be
>>> detected on what you can see with the unaided eye, then you are up for a
>>> big surpirse. It doesn't work !
>> Detected with what?
> With the eye !
That doesn't make any sense. A "formula of how dim objects that can be
detected" with the eye, based on what you can see with the eye, ought to
work! It's self-referential.
>>> So if the unaided can barely detect a mag 7.0 object on a given night, a
>>> telescope might still allow detection of something like mag 8.0 +
>>> 5.0*log(D/7.0), if a proper magnification is choosen...or sometimes even
>>> better...
>> Can you explain that?
> A higher magnification (esp higher than giving a 7mm exit-pupil) can improve
> the image in several ways.
Let's ignore exit pupils that are larger than the eye's entrance pupil.
> 1. A smaller exit-pupil uses a better part of the eye's pupil, thus making
> the object more distinct.
What makes the central region of the eye's pupil "better"?
> 2. The eye is not a linear device, and a larger magnification will some
> times (many times) improve the contrast against the background. A linear
> device can not do this.
For objects that are truly point sources. But see above.
> 3. The eye does not use single-pixel detection, and the eye uses some very
> sofisticated imageprocessing software, implemented in a neural net.
And when the brain knows that there is supposed to be a very faint object
in the field, it can easily imagine that it saw the object. A real test
would involve pointing the telescope at a field unknown to the observer
and letting that person sketch what he sees, then comparing it to what we
know the sky to really look like.
> Not having a scientificly explained model for the eye, this can not be
> proven with mathematics, but clearly the eye can be proven to _not_ be
> linear using a very simple test.
That the eye is not a linear device is not the issue.
> Detection of faint objects can easily be shown to be improved when using
> higher magnificatiosn.
Which is a restatement of the original claim for which I'm requesting an
explanation.
> Just try to located an object close to the limits of
> the telescope using
> 1. 5 exit-pupil, and...
> 2. 1 mm exit-pupil
>
> ....and compare the results.
How about comparing the limiting magnitude for the naked eye and for the
aided eye?
> Pluto is fex simple in my telescope (12") at around 260x on a dark night,
> but impossible at 78x (perhaps not impossible, but I have not succeded
> yet)...
Fex?
A 12-inch telescope is not a 3.7-inch telescope. I expect Pluto to be
visible through a 12-inch.
tho...@antispam.ham
> [...]
>>> I didn't say magnify too much...
>> Any kind of magnification spreads out the photons.
> First of all that is incorrect - a point-like source will not be spread out
> by magnification as long as the object remains pointlike.
Dealt with previously.
> Secondly, you are refering to a linear device like a ccd-camera, not to the
> eye...
Dealt with previously.
>>>>> Although detecting a mag 8 object with the unaided eye may be
>>>>> extremely difficult, detecting it under similar circumstances
>>>>> with a higher magnification can be much easier...
>>>> Magnification involves some optics, and those optics could be
>>>> gathering more light than the eye alone could do.
>>> Yes, it can. But if you base a formula of how dim objects that can be
>>> detected on what you can see with the unaided eye, then you are up for a
>>> big surpirse. It doesn't work !
>> Detected with what?
> The eye !
Dealt with previously.
>>> So if the unaided can barely detect a mag 7.0 object on a given night, a
>>> telescope might still allow detection of something like mag 8.0 +
>>> 5.0*log(D/7.0), if a proper magnification is choosen...or sometimes even
>>> better...
>> Can you explain that?
> Certainly:
>
> A higher magnification (higher than giving 7mm especially) improves the
> image
> 1. By using a better portion of the eye, and causing less aberrations inside
> the eye
> 2. Since the eye is not linear, changing magnification can (many times do)
> improve the contrast between the object and the background. A linear device
> will not do this.
> 3. The eye does not use single-pixel detection, having a diffuse object
> sometomes actually do improve detection. This is probably since the eye uses
> a sophisticated imageprocessing software implemented in a neural net.
Dealt with previously.
> 4. The darker backround at higher magnification allows the eye to darkadapt
> bettter and the object will then be simpler to detect.
As long as the exit pupil is smaller than the eye's entrance pupil, how
can the eye dark adapt better?
> Certainly there are also losses in the telescope, not all light will reach
> the eye when passing through an optical system. What I am arguing here is
> that observations support that the gains of using higher magnifications many
> times outwieghs the losses and improves the detection formula beyound what
> is possible to detect with the unaided eye.
What you are doing is restating the original claim. What I'm after is an
explanation.
> In my 12" telescope I easily detect Pluto at 260x on a dark night, but I
> have yet to succeed at 78x. In fact I have detected pluto once in my 6"
> telescope which according to common formulas should not be able to pick out
> Pluto. Magnification was 360x when I did this, failed at lower
> magnifications.
Dealt with previously.
> At my site, I can on a good night detect about mag 6.5 with one eye, and I
> think my pupil is about 7mm when largest. My 12" telescope gathers about
> 1900 times more light, but only 70% reaches my eye. That gives about 1330
> times brighter stars, or 7.8 mag extra detection. According to this I should
> be able to detect mag 14.3, which is reasonable. Pluto is simple on a good
> night. But my 6" should only be able to detect about mag 12.8, and Pluto is
> always dimmer than this, yet I have managed to detect it once,
How can you be sure? If you were specifically looking for it, you could
have imagined seeing it.
> and others also report detection with even smaller instruments.
And they could have imagined seeing it as well.
> A linear model simply does not work...
Which is essentially another restatement of the claim.
> Adjusting the simple formula m0 + 5.0*log( D / d) for magnification suggest
> thah m0 is increasing a little as magnification goes up, perhaps as much as
> 1.0-1.5 mag, before the negative effects of spreading the light out becomes
> to large.
What I'm looking for is an explanation for this alleged phenomenon.
> Clearly, magic can not be done, but using a linear model for the eye, and
> what it can detect, will fail...
Which is essentially another restatement of the claim.
Brian Tung
> I'm not convinced. It's very easy to imagine that you saw something very
> briefly, especially when you know there is something there to be seen.
> What you really need is a test involving a field where the observer does
> not know what is supposed to be there.
Point taken. However, I'll note that if that's the case for test objects
(like the stars I saw through the 5 mm masked-down binocs--and I did *not*
know which stars were which before I checked them later against a star
atlas program), it's also the case for Pluto. With computer planetarium
programs and accurate orbital elements, today's amateurs looking for Pluto
often know very well just where it is.
tho...@antispam.ham
>> I'm not convinced. It's very easy to imagine that you saw something very
>> briefly, especially when you know there is something there to be seen.
>> What you really need is a test involving a field where the observer does
>> not know what is supposed to be there.
> Point taken. However, I'll note that if that's the case for test objects
> (like the stars I saw through the 5 mm masked-down binocs--and I did *not*
> know which stars were which before I checked them later against a star
> atlas program), it's also the case for Pluto. With computer planetarium
> programs and accurate orbital elements, today's amateurs looking for Pluto
> often know very well just where it is.
Which makes Pluto not a very good test, given how easy it is to prepare
for the test.
Magnus Nyborg
Sorry for the double post - Outlook Explorer crashed and I did not think
that the post was sent soo I had to start all over again...
<tho...@AntiSpam.ham> wrote in message
news:csCN6.3569$WI.8...@typhoon.hawaii.rr.com...
> Magnus Nyborg writes:
>
> > [...]
>
> >>> I didn't say magnify too much...
>
> >> Any kind of magnification spreads out the photons.
>
> > First of all, this not apply for an object when it is point-like
>
> But everything observed through the Earth's atmosphere isn't point-like.
> It's also true that even without the atmosphere, the image produced by
> optics of a finite size will have a point-spread-function that will
> spread out the photons with magnification. So it effectively applies
> to everything.
Stars are for all practical purposes pinpoints up to magnification of about
150x in a 12" at my location on most nights.
>
> > Second, the eye does not react like a ccd-camera. Magnifying more can,
> > as witnessed by many, help in detecting a diffuse object.
>
> First of all, I have a camcorder with a CCD in it, and it can pick up
> first magnitude stars when I zoom in, but those stars will disappear
> when I zoom out, so a CCD camera apparently can react like how you
> believe the eye reacts. Second of all, we're talking about Pluto
> here, not a diffuse object.
Does the camcorder have auto-dark set for the background ?
Don't compare a camcorder with an eye, there is no comparison. They don't
work the same !
>
> >>>>> Although detecting a mag 8 object with the unaided eye may be
> >>>>> extremely difficult, detecting it under similar circumstances
> >>>>> with a higher magnification can be much easier...
>
> >>>> Magnification involves some optics, and those optics could be
> >>>> gathering more light than the eye alone could do.
>
> >>> Yes, it can. But if you base a formula of how dim objects that can be
> >>> detected on what you can see with the unaided eye, then you are up for
a
> >>> big surpirse. It doesn't work !
>
> >> Detected with what?
>
> > With the eye !
>
> That doesn't make any sense. A "formula of how dim objects that can be
> detected" with the eye, based on what you can see with the eye, ought to
> work! It's self-referential.
Siliness! If the model is incorrect, it does not matter if you think it is
selfreferential ! Being selfreferential is not a guarantee for
correctness...
>
> >>> So if the unaided can barely detect a mag 7.0 object on a given night,
a
> >>> telescope might still allow detection of something like mag 8.0 +
> >>> 5.0*log(D/7.0), if a proper magnification is choosen...or sometimes
even
> >>> better...
>
> >> Can you explain that?
>
> > A higher magnification (esp higher than giving a 7mm exit-pupil) can
improve
> > the image in several ways.
>
> Let's ignore exit pupils that are larger than the eye's entrance pupil.
>
> > 1. A smaller exit-pupil uses a better part of the eye's pupil, thus
making
> > the object more distinct.
>
> What makes the central region of the eye's pupil "better"?
Mainly since the smaller exit-pupil of the eyepiece reduces the aberrations
induced by the eye's single (chromatic and spherical aberration) lens. A
F/2 eye _must_ be much worse than an F/10 eye (not knowing the real
parameters here). The brain processes much of the chromatic and possibly
spherical aberrations out.
>
> > 2. The eye is not a linear device, and a larger magnification will some
> > times (many times) improve the contrast against the background. A linear
> > device can not do this.
>
> For objects that are truly point sources. But see above.
Not only for objects that are pinpoints, the effect is often referred to
while locating dim fuzzies...
>
> > 3. The eye does not use single-pixel detection, and the eye uses some
very
> > sofisticated imageprocessing software, implemented in a neural net.
>
> And when the brain knows that there is supposed to be a very faint object
> in the field, it can easily imagine that it saw the object. A real test
> would involve pointing the telescope at a field unknown to the observer
> and letting that person sketch what he sees, then comparing it to what we
> know the sky to really look like.
Yes, a real test takes a lot of preparations - would you like to carry them
out. If you don't, stop hiding behind a blanket of selfricheousness...
My observations are reported by others, and I am experienced enough to avoid
fooling myself about detecting a star or something. If I have a 50/50
detection, I say soo...
>
> > Not having a scientificly explained model for the eye, this can not be
> > proven with mathematics, but clearly the eye can be proven to _not_ be
> > linear using a very simple test.
>
> That the eye is not a linear device is not the issue.
Ooh, but it is - you not understanding that it is, does not change the fact
! The eye being an non-linear device is what causes many of the observed
situations...
A linear device would follow the formula m0 + 5*log( D / d) slavishly,
regardless of magnification. The reported behaviour is _not_ following the
formula, many contradictions reported, QED: The linear formula is not
correct!
The behaviour is more that of an initially increasing m0 (from perhaps 6.5
to maybe 8.0) as magnification becomes larger and closes in on around 1mm
exit-pupil.
[Disclaimer: Even if the behaviour of the eye is not linear, it can be made
up of linear devices]
>
> > Detection of faint objects can easily be shown to be improved when using
> > higher magnificatiosn.
>
> Which is a restatement of the original claim for which I'm requesting an
> explanation.
The evidence is only indicative, I have checked myself and talked to a few
people, that's all. I know of no thourough study of this phenomenon, but
many have reported what appears as confirmation. Sorry, I am only one guy,
as representative as I hope I am.
My claims are that:
1. The eye is not linear
2. That m0 (in the formule m0 + 5*log(D / d) is dependant of magnification
(which is the same as saying that the eye is not linear) and increases a
little when going from a 7mm exit-pupil to a 1mm pupil. More factors than
this have to be considered, like seeing, transparenty, lightpollution etc,
but what remains is a clear indication that m0 is magnification-dependant.
Perhaps if you looked through your own scope and tested detecting dim
objects that you would become convinced that at least the linear model for
the eye is not complete.
>
> > Just try to located an object close to the limits of
> > the telescope using
> > 1. 5 exit-pupil, and...
> > 2. 1 mm exit-pupil
> >
> > ....and compare the results.
>
> How about comparing the limiting magnitude for the naked eye and for the
> aided eye?
That suggest a non-linear fit !! I have tried to do this, have you ?
>
> > Pluto is fex simple in my telescope (12") at around 260x on a dark
night,
> > but impossible at 78x (perhaps not impossible, but I have not succeded
> > yet)...
>
> Fex?
For example
>
> A 12-inch telescope is not a 3.7-inch telescope. I expect Pluto to be
> visible through a 12-inch.
Do you expect to see it at 78x ?
Even soo, I have spotted it in my 6" once (on a very good night) - I know I
spotted it, because the 6":er (MK67) was piggybacked on the 12":er (LX200)
making one heck-of-a impressive double-barrel shotgun !! I did this
expecting not to see Pluto, but it turned out that I could easily make it
out when using averted vision along a few stars of similar brightness. A
90/10 detection with the 6":er if you want to know how certain I am, and
clear a confirmation using the 12":er.
Now, my eye's are perhaps not the most sensitive ones, it is difficult for
me to say anything about somebody elses detection in a 3.7":er, perhaps it
is possible. At least my experience tells me that many things usually
considered impossible turns out to be possible when done correctly.
Detection of Pluto with a 6":er is also considered impossible when using a
most models...
Clear Skies,
Magnus
>
tho...@antispam.ham
>>> [...]
>>>>> I didn't say magnify too much...
>>>> Any kind of magnification spreads out the photons.
>>> First of all, this not apply for an object when it is point-like
>> But everything observed through the Earth's atmosphere isn't point-like.
>> It's also true that even without the atmosphere, the image produced by
>> optics of a finite size will have a point-spread-function that will
>> spread out the photons with magnification. So it effectively applies
>> to everything.
> Stars are for all practical purposes pinpoints up to magnification of about
> 150x in a 12" at my location on most nights.
What are "practical purposes" in the context of this discussion?
>>> Second, the eye does not react like a ccd-camera. Magnifying more can,
>>> as witnessed by many, help in detecting a diffuse object.
>> First of all, I have a camcorder with a CCD in it, and it can pick up
>> first magnitude stars when I zoom in, but those stars will disappear
>> when I zoom out, so a CCD camera apparently can react like how you
>> believe the eye reacts. Second of all, we're talking about Pluto
>> here, not a diffuse object.
> Does the camcorder have auto-dark set for the background ?
No.
> Don't compare a camcorder with an eye, there is no comparison.
In the case of magnification enhancing detectability, one can make a
comparison, and in this case, the camcorder performed in a way that
you've been claiming for the eye.
> They don't work the same !
Irrelevant, given that I didn't say they do.
>>>>>>> Although detecting a mag 8 object with the unaided eye may be
>>>>>>> extremely difficult, detecting it under similar circumstances
>>>>>>> with a higher magnification can be much easier...
>>>>>> Magnification involves some optics, and those optics could be
>>>>>> gathering more light than the eye alone could do.
>>>>> Yes, it can. But if you base a formula of how dim objects that can be
>>>>> detected on what you can see with the unaided eye, then you are up for
>>>>> a big surpirse. It doesn't work !
>>>> Detected with what?
>>> With the eye !
>> That doesn't make any sense. A "formula of how dim objects that can be
>> detected" with the eye, based on what you can see with the eye, ought to
>> work! It's self-referential.
> Siliness! If the model is incorrect, it does not matter if you think it is
> selfreferential ! Being selfreferential is not a guarantee for
> correctness...
It is a guarantee for circular reasoning in this case.
>>>>> So if the unaided can barely detect a mag 7.0 object on a given night,
>>>>> a telescope might still allow detection of something like mag 8.0 +
>>>>> 5.0*log(D/7.0), if a proper magnification is choosen...or sometimes
>>>>> even better...
>>>> Can you explain that?
>>> A higher magnification (esp higher than giving a 7mm exit-pupil) can
>>> improve the image in several ways.
>> Let's ignore exit pupils that are larger than the eye's entrance pupil.
>>> 1. A smaller exit-pupil uses a better part of the eye's pupil, thus
>>> making the object more distinct.
>> What makes the central region of the eye's pupil "better"?
> Mainly since the smaller exit-pupil of the eyepiece reduces the aberrations
> induced by the eye's single (chromatic and spherical aberration) lens. A
> F/2 eye _must_ be much worse than an F/10 eye (not knowing the real
> parameters here). The brain processes much of the chromatic and possibly
> spherical aberrations out.
And how does the convergence of the light cone affect transmission?
>>> 2. The eye is not a linear device, and a larger magnification will some
>>> times (many times) improve the contrast against the background. A linear
>>> device can not do this.
>> For objects that are truly point sources. But see above.
> Not only for objects that are pinpoints, the effect is often referred to
> while locating dim fuzzies...
How does magnification improve contrast on "dim fuzzies"?
>>> 3. The eye does not use single-pixel detection, and the eye uses some
>>> very sofisticated imageprocessing software, implemented in a neural net.
>> And when the brain knows that there is supposed to be a very faint object
>> in the field, it can easily imagine that it saw the object. A real test
>> would involve pointing the telescope at a field unknown to the observer
>> and letting that person sketch what he sees, then comparing it to what we
>> know the sky to really look like.
> Yes, a real test takes a lot of preparations - would you like to carry them
> out.
Sure, I'd be happy to. Would you like to fund them?
> If you don't, stop hiding behind a blanket of selfricheousness...
I'm not hiding at all; I'm discussing the issue right here, out in the
open. Furthermore, you're erroneously presupposing the existence of
some "blanket of selfricheousness".
> My observations are reported by others,
Which by definition makes them second hand.
> and I am experienced enough to avoid fooling myself about detecting a
> star or something.
Doesn't that mean you're sure one way or the other?
> If I have a 50/50 detection, I say soo...
Which means you're not sure, which means you might be fooling yourself.
>>> Not having a scientificly explained model for the eye, this can not be
>>> proven with mathematics, but clearly the eye can be proven to _not_ be
>>> linear using a very simple test.
>> That the eye is not a linear device is not the issue.
> Ooh, but it is -
On the contrary, the issue is detectability as a function of magnification.
> you not understanding that it is,
Balderdash; you can't pontificate about my alleged misunderstanding and
use that to justify a change in the issue.
> does not change the fact
> ! The eye being an non-linear device is what causes many of the observed
> situations...
The eye being non-linear is why the magnitude system is logarithmic.
That doesn't prove that magnification enchances detectability.
> A linear device would follow the formula m0 + 5*log( D / d) slavishly,
> regardless of magnification.
A non-linear device could also follow some formula slavishly, regardless
of magnification.
> The reported behaviour is _not_ following the formula,
*Your* reported behavior does not follow the formula.
> many contradictions reported,
No sufficient explanation provided.
> QED: The linear formula is not correct!
That doesn't logically follow. It has happened on many occasions that
someone can get the right answer for the wrong reasons. You've personally
observed a phenomenon; just because you've been able to come up with only
one explanation for that phenomenon does not guarantee that your
explanation is the correct one. See below for some other options.
> The behaviour is more that of an initially increasing m0 (from perhaps 6.5
> to maybe 8.0) as magnification becomes larger and closes in on around 1mm
> exit-pupil.
What is special about 1 mm? Why not 0.5 mm? 0.1 mm?
> [Disclaimer: Even if the behaviour of the eye is not linear, it can be made
> up of linear devices]
Also irrelevant to the issue of magnification enhancing detectability.
>>> Detection of faint objects can easily be shown to be improved when using
>>> higher magnificatiosn.
>> Which is a restatement of the original claim for which I'm requesting an
>> explanation.
> The evidence is only indicative, I have checked myself and talked to a few
> people, that's all.
I have my own experience as well.
> I know of no thourough study of this phenomenon,
Yet you seem to be convinced of the One True explanation, namely
magnification.
> but many have reported what appears as confirmation.
If one person can imagine seeing something below what is normally considered
the threshold of detectability, then it is reasonable to assume that others
could also imagine seeing something below what is normally considered the
threshold of detectability. This discussion isn't too different from the
ones involving speaker wire, for example. Can you hear a difference?
Perhaps you've read about double-blind testing? Has it been done in this
case?
> Sorry, I am only one guy, as representative as I hope I am.
And it's entirely possible for one guy to honestly claim that they saw
Pluto through a 3.7-inch telescope without having actually seen it,
given that the imagination can take over when working near thresholds,
especially when they know something is supposed to be there.
> My claims are that:
> 1. The eye is not linear
Irrelevant, given that I never said it isn't.
> 2. That m0 (in the formule m0 + 5*log(D / d) is dependant of magnification
> (which is the same as saying that the eye is not linear)
On the contrary, those are substantially different claims. A detector
can have non-linear response and still be independent of some effect.
> and increases a little when going from a 7mm exit-pupil to a 1mm pupil.
Can you explain that?
> More factors than this have to be considered, like seeing, transparenty,
> lightpollution etc,
Not when the claim in question is restricted to magnification.
> but what remains is a clear indication that m0 is magnification-dependant.
How can you be sure? To change magnification, you presumably changed the
eyepiece. Maybe the shorter focal length eyepiece had fewer optical
elements and transmitted more light. Maybe it had better antirelection
coatings. Maybe it had a better design to correct for various kinds of
aberrations. Yet for some reason, you're convinced that none of those
are factors, and that it MUST be magnification.
> Perhaps if you looked through your own scope and tested detecting dim
> objects that you would become convinced that at least the linear model for
> the eye is not complete.
I have, and I do not have any evidence to support the conclusion that
magnification enhances detectability. I have not discussed any linear
model for the eye. The eye, like the ear, is known to not be a linear
detector. That's why stars visible to the naked eye range in brightness
by about a factor of 100 (excluding the Sun) but were assigned magnitudes
that range (historically) from about 1st to 6th magnitude.
>>> Just try to located an object close to the limits of
>>> the telescope using
>>> 1. 5 exit-pupil, and...
>>> 2. 1 mm exit-pupil
>>>
>>> ....and compare the results.
>> How about comparing the limiting magnitude for the naked eye and for the
>> aided eye?
> That suggest a non-linear fit !!
The issue isn't whether the response of the eye is non-linear, but
rather whether the magnification made a difference in the detectability.
> I have tried to do this, have you ?
I have tried to see objects near the threshold of detectability for
telescopes of given apertures.
>>> Pluto is fex simple in my telescope (12") at around 260x on a dark
>>> night, but impossible at 78x (perhaps not impossible, but I have not
>>> succeded yet)...
>> Fex?
> For example
You act as if that is common knowledge. I've never seen it used before.
>> A 12-inch telescope is not a 3.7-inch telescope. I expect Pluto to be
>> visible through a 12-inch.
> Do you expect to see it at 78x ?
I expect aperture to be more important than magnification.
> Even soo, I have spotted it in my 6" once (on a very good night)
A 6-inch telescope is not a 3.7-inch telescope.
> - I know I spotted it, because the 6":er (MK67) was piggybacked on the
> 12":er (LX200) making one heck-of-a impressive double-barrel shotgun !!
How does that prove that you saw it through the 6-inch? The imagination
can take over, especially in this situation, given that you knew what to
expect from the view through the 12-inch.
> I did this expecting not to see Pluto,
But you knew where to expect it. So one brief spot could be misinterpreted
as Pluto becoming visible during a moment of really good seeing, when it
could just be some physical effect unrelated to any photon stimulus.
> but it turned out that I could easily make it
> out when using averted vision along a few stars of similar brightness.
Having had the larger telescope to show you what to expect. Not a very
good test. Get someone to point the 6-inch telescope at several points
in the sky without your knowledge of the contents of the fields. Sketch
what you see. Then compare with reality. That would be a much better
test of the true limiting magnitude.
> A 90/10 detection with the 6":er if you want to know how certain I am,
> and clear a confirmation using the 12":er.
My own tests had a built-in means of confirmation. If what I saw was
real, then I should have been able to center the object in the aperture
of a single aperture photometer and measure the brightness. The
published results show just how faint it was possible to work (and there
was plenty of magnification).
> Now, my eye's are perhaps not the most sensitive ones,
That the sensitivity of eyes varies from person to person is well known.
> it is difficult for me to say anything about somebody elses detection
> in a 3.7":er,
Did you notice that I didn't say anything about whether that person's
detection was real or not? I simply noted that such a detection implies
that that person's naked eye should be able to see magnitude 8. That's
when the suggestion was made that such a conclusion doesn't necessarily
follow due to the alleged magnification effect.
> perhaps it is possible.
I'd like to see the test performed.
> At least my experience tells me that many things usually
> considered impossible turns out to be possible when done correctly.
My experience tells me that something thought to be possible wasn't
really possible when a scientific study is done correctly. Do at
least a single-blind test sometime.
> Detection of Pluto with a 6":er is also considered impossible when using
> a most models...
Considered impossible by whom?
Nancy Lieder
wrote:
> Nancy Lieder writes:
>> Neuchatal folks (who did not get offical permission to release
>> the information) got an image, but this was never received,
>
> How convenient for you. Interesting that you haven't accused
> them of cover-up the way you've accused NASA for HST images
> that were allegedly never released.
That NASA withholds HST images, only selectively giving them out, is not
an accusation, it's a fact. Do cover-ups exists, and do folks get leaned
on? Are lies foisted on the public? As examples:
1. JFK was killed by a single bullet. He and the others
in the car were wounded by only a single bullet,
which traveled through several bodies making sharp
turns and impacting bone in some cases but emerged
intact. This was the official explanation, in place
today.
2. George Bush Sr., former head of the CIA, was not in
the loop on Iran Contra. Iran Contra would have been
a secret operation, unknown to the public today, if
there hadn't been an accident exposing the operation.
Here we had an illegal operation, headquartered in
the basement of the White House, with the President
in the know.
What kind of tactics are used to maintain a cover-up? I was told in the
early days of Hale-Bopp, when I asked someone with a NASA security
clearance, if NASA would lie about Hale-Bopp. He told me that the first
newspaper story released was laced with code words that meant "do not
challenge this story". Steve Havas, who has posted about his sighting
of Planet X at a Vancouver observatory, was told verbally by an
associated astronomer, in a hushed voice, that they know about this
inbound planet, and thus the frantic stalling tactics he encountered and
recorded. I likewise was told in California by an astronomer who worked
at one of the major observatories that "at first we were looking for it,
then we found it, and now we're tracking it. It comes through the solar
system every few thousand years, and pretty much tears up the earth." So
why don't they get on the bullhorn and blab? Are they afraid of losing
a job or being put in a wacky ward with the subsequent claim they were
crazy at the time they made claims, or physically threatened? Were it
not that Planet X CAN'T be hidden anymore, as it is visible by
observatories world-wide, so that only an "alternate explanation" can
perpetrate the cover-up at this point, I'd expect folks like Steve to be
leaned on too. Here's a silencing method used in the past:
The Alien Question: An Expanded Perspective
by Neil Freer
Tombaugh discovered Pluto in 1930. Christie, of the U.S.
Naval Observatory, discovered Charon, Pluto's moon, in
1978. The characteristics of Pluto derivable from the
nature of Charon demonstrated that there must still be a
large planet undiscovered because Pluto could not be the
cause of the residuals, the "wobbles" in the orbital paths of
Uranus and Neptune clearly identifiable. The IRAS
(Infrared Astronomical Satellite), during '83 -'84, produced
observations of a tenth planet so robust that one of the
astronomers on the project said that "all that remains is to
name it" - from which point the information has become
curiously guarded. In 1992 Harrington and Van Flandern
of the Naval Observatory, working with all the information
they had at hand, published their findings and opinion
that there is, indeed, a tenth planet, even calling it an
"intruder" planet. Andersen of JPL later publicly expressed
his belief that it could possibly be verified any time. The
search was narrowed to the southern skies, below the
ecliptic. Harrington invited Sitchin, having read his book
and translations of the Enuma Elish, to a meeting at his
office and they correlated the current findings with the
ancient records and Harrington acknowledged the detail of
the ancient records while indicating where the tenth planet
may now be in the solar system.
It is the opinion of this author that, in light of the evidence
already obtained through the use of the Pioneer 10 and
11 and two Voyager space craft, the Infrared Imaging
Satellite (IRAS, `83-84) and the data available to Harrington
when consulting with Sitchin that the search has already
been accomplished, in fact that the planet has already
been found. It is interesting that Harrington dispatched an
appropriate telescope to Black Birch, New Zealand to
get a visual confirmation, based on the data leading to
the expectation that it would be below the ecliptic in the
southern skies at this point in its orbit. On Harrington's
early death the scope was immediately called back - as one
observer noted, "almost before he was cold". ...
Robert Harrington used to be the head of the Naval Observatory, and Tom
van Flandern worked closely with Harrington at the US Naval Observatory.
Nancy Lieder
wrote:
> Nancy Lieder writes:
>> OK, so Pluto can be seen, as something other than a pin-point,
>> as it is MAGNIFIED by observatories.
>
> Actually, only HST has ever imaged it as something other than
> a pin-point, and that's because of the lack of atmospheric
> turbulence, coupled with a long focal length, giving an image
> scale that allowed several pixels across the disk.
Thanks, Dave, for acknowledging that an object APPEARING not much larger
than Pluto at the present time would be difficult to be seen by amateurs
unless strong magnification such as observatory scopes have were
available to assist. Planet X is about 9 Sun-Pluto spans from Earth at
present, but closing fast over the next two years.
In Article <4KhN6.3080$WI.5...@typhoon.hawaii.rr.com> Daivd Tholen
wrote:
> Nancy Lieder writes:
>> And it appears as a "blob" (i.e. DIFFUSE, not a pin-point) to some.
>
> Actually, it appears as just as much a "blob" as any other star
> suffering from atmospheric turbulence. The seeing is a
> function of the atmosphere, not the telescope.
Big difference between 1. Pluto and 2. stars and 3. Planet X is that 1.
Pluto REFLECTS sunlight, and this is what makes if visible to amateurs
at all, 2. stars have a great intensity of light coming from the center
of the pin-point, allowing them to be seen at great distances, 3. Planet
X emits light and obviously light in the infrared spectrum, being a
smoldering brown dwarf, but does not reflect sunlight.
tho...@antispam.ham
>>> Neuchatal folks (who did not get offical permission to release
>>> the information) got an image, but this was never received,
>> How convenient for you. Interesting that you haven't accused
>> them of cover-up the way you've accused NASA for HST images
>> that were allegedly never released.
> That NASA withholds HST images, only selectively giving them out,
> is not an accusation, it's a fact.
It's a fact that every professional telescope doesn't give out every
single image it's ever taken. The sheer volume of data would be
unmanageable. If you disagree, why don't you present your plan
for making every single image available for general public access?
Keep in mind that a single night with the 12k CCD on CFHT can produce
something like 30 gigabytes of data.
> I was told in the early days of Hale-Bopp, when I asked someone with
> a NASA security clearance, if NASA would lie about Hale-Bopp.
Who is this "someone"?
> He told me that the first newspaper story released was laced with
> code words that meant "do not challenge this story".
Hogwash.
> Steve Havas, who has posted about his sighting of Planet X at a
> Vancouver observatory, was told verbally by an associated astronomer,
> in a hushed voice, that they know about this inbound planet, and thus
> the frantic stalling tactics he encountered and recorded.
Who is this alleged "associated astronomer"?
> I likewise was told in California by an astronomer who worked
> at one of the major observatories that "at first we were looking for it,
> then we found it, and now we're tracking it.
Who is this alleged "astronomer who worked at one of the major
observatories"?
> It comes through the solar system every few thousand years, and pretty
> much tears up the earth."
So where's the evidence that the Earth was torn up a few thousand years
ago?
> So why don't they get on the bullhorn and blab?
You're presupposing that "they" exist. Care to name some names?
> Are they afraid of losing a job or being put in a wacky ward with the
> subsequent claim they were crazy at the time they made claims, or
> physically threatened?
What are you afraid of by not naming names?
> Were it not that Planet X CAN'T be hidden anymore,
Then why are people having such trouble seeing it?
> as it is visible by observatories world-wide,
Really? It hasn't been seen from Mauna Kea.
> so that only an "alternate explanation" can perpetrate the cover-up
> at this point,
You're erroneously presupposing that the object exists.
> I'd expect folks like Steve to be leaned on too.
By whom?
> Here's a silencing method used in the past:
>
> The Alien Question: An Expanded Perspective
> by Neil Freer
>
> Tombaugh discovered Pluto in 1930. Christie, of the U.S.
> Naval Observatory, discovered Charon, Pluto's moon, in
> 1978. The characteristics of Pluto derivable from the
> nature of Charon demonstrated that there must still be a
> large planet undiscovered because Pluto could not be the
> cause of the residuals, the "wobbles" in the orbital paths of
> Uranus and Neptune clearly identifiable.
The cause of the residuals in the orbit of Uranus was two-fold:
errors in the star catalog used to determine the position of
Uranus in the late 19th century, and a bad mass for Neptune,
which was resolved following the Voyager 2 flyby in 1989.
Of course, I've explained this before.
You're way behind the times, Nancy. Or do you selectively ignore
more recent publications that destroy your case?
tho...@antispam.ham
>>> OK, so Pluto can be seen, as something other than a pin-point,
>>> as it is MAGNIFIED by observatories.
>> Actually, only HST has ever imaged it as something other than
>> a pin-point, and that's because of the lack of atmospheric
>> turbulence, coupled with a long focal length, giving an image
>> scale that allowed several pixels across the disk.
> Thanks, Dave, for acknowledging that an object APPEARING not much larger
> than Pluto at the present time
Previously you claimed that your object is smaller than Pluto. Now
it's "not much larger". Yet another inconsistency.
> would be difficult to be seen by amateurs unless strong magnification
> such as observatory scopes have were available to assist.
I said absolutely nothing above about the difficulty of seeing Pluto.
I was talking about the disk of Pluto being resolved. Strong
magnification does nothing to remove atmospheric seeing or
diffraction limits.
>>> And it appears as a "blob" (i.e. DIFFUSE, not a pin-point) to some.
>> Actually, it appears as just as much a "blob" as any other star
>> suffering from atmospheric turbulence. The seeing is a
>> function of the atmosphere, not the telescope.
> Big difference between 1. Pluto and 2. stars and 3. Planet X is that 1.
> Pluto REFLECTS sunlight,
Whether the light was reflected or emitted is irrelevant once it has
left the object. It has no knowledge of how it was produced.
> and this is what makes if visible to amateurs at all, 2. stars have
> a great intensity of light coming from the center of the pin-point,
It is ridiculous to refer to the center of a pin-point. A point is
just that, a point.
> allowing them to be seen at great distances,
Brightness is what allows a star to be seen at great distances, not
whether the light originates from the center or edge of a "pin-point"
(still a ridiculous notion).
> 3. Planet X emits light and obviously light in the infrared spectrum,
But human eyes cannot "see" infrared light, so how did Havas manage
to see it? And how could it possible have a visual magnitude of 11
if it doesn't emit any visible light?
> being a smoldering brown dwarf, but does not reflect sunlight.
Which contradicts your claim of "red iron dust".
Bill Nelson
:>
:> Actually, only HST has ever imaged it as something other than
:> a pin-point, and that's because of the lack of atmospheric
:> turbulence, coupled with a long focal length, giving an image
:> scale that allowed several pixels across the disk.
: Thanks, Dave, for acknowledging that an object APPEARING not much larger
: than Pluto at the present time would be difficult to be seen by amateurs
: unless strong magnification such as observatory scopes have were
: available to assist. Planet X is about 9 Sun-Pluto spans from Earth at
: present, but closing fast over the next two years.
He didn't say that. He stated that Pluto has only appeared as a point
in ground based telescopes. The same would be true of this object, if
it existed. Whether it is diffuse or not is immaterial, as it is the
angular diameter covered that determines whether the object is diffuse
or a point source. As this reputed object is supposedly not thousands
of times larger than Pluto, it will appear as a point source. It would
do so, even in the Hubble scope.
--
Bill Nelson (bi...@peak.org)
joe ken
> already obtained through the use of the Pioneer 10 and
> 11 and two Voyager space craft, the Infrared Imaging
> Satellite (IRAS, `83-84) and the data available to Harrington
> when consulting with Sitchin that the search has already
> been accomplished, in fact that the planet has already
> been found. It is interesting that Harrington dispatched an
> appropriate telescope to Black Birch, New Zealand to
> get a visual confirmation, based on the data leading to
> the expectation that it would be below the ecliptic in the
> southern skies at this point in its orbit. On Harrington's
> early death the scope was immediately called back - as one
> observer noted, "almost before he was cold". ...
Anyone of the "big fish" want to comment on this? Tholen, Knisely,
Neill, Schlyter?
maybe Van Flandern, Neugebauer, Scotti or others care to comment on
the occupational hazards of astronomy :O
joe ken
Washington Post
Mystery Heavenly Body Discovered 31-Dec-1983
A heavenly body possibly as large as the giant planet Jupiter and
possibly so close to Earth that it would be part of this solar system
has been found in the direction of the constellation Orion by an
orbiting telescope aboard the U.S. infrared astronomical satellite...
... "All I can tell you is that we don't know what it is," Dr. Gerry
Neugebauer, IRAS chief scientist for California's Jet Propulsion
Laboratory and director of the Palomar Observatory for the California
Institute of Technology said in an interview...
The mystery body was seen twice by the infrared satellite as it
scanned the northern sky from last January to November...
When IRAS scientists first saw the mystery body and calculated that it
could be as close as 50 billion miles, there was some speculation that
it might be moving toward Earth. "It's not incoming mail," Cal Tech's
Neugebauer said. "I want to douse that idea with as much cold water as
I can."
Paul Schlyter
joe ken <brain...@yahoo.com> wrote:
>> It is the opinion of this author that, in light of the evidence
>> already obtained through the use of the Pioneer 10 and
>> 11 and two Voyager space craft, the Infrared Imaging
>> Satellite (IRAS, `83-84) and the data available to Harrington
>> when consulting with Sitchin that the search has already
>> been accomplished, in fact that the planet has already
>> been found. It is interesting that Harrington dispatched an
>> appropriate telescope to Black Birch, New Zealand to
>> get a visual confirmation, based on the data leading to
>> the expectation that it would be below the ecliptic in the
>> southern skies at this point in its orbit. On Harrington's
>> early death the scope was immediately called back - as one
>> observer noted, "almost before he was cold". ...
>
> Anyone of the "big fish" want to comment on this? Tholen, Knisely,
> Neill, Schlyter?
since I don't remember having seen that post.
Anyway, one good rule of thumb is: if someone claims the solar system
has a new major planet, and if (s)he uses Sitchin as a reference, you
can be quite certain it's a hoax.
If there's a new planet there, it ought to have been seen by many
observers. Even if it's far south in the sky - the southern
hemisphere has many good observers too!
> maybe Van Flandern, Neugebauer, Scotti or others care to comment on
> the occupational hazards of astronomy :O
----------------------------------------------------------------
Paul Schlyter, Swedish Amateur Astronomer's Society (SAAF)
Grev Turegatan 40, S-114 38 Stockholm, SWEDEN
e-mail: pausch at saaf dot se or paul.schlyter at ausys dot se
WWW: http://hotel04.ausys.se/pausch http://welcome.to/pausch
David W Knisely
> As for the
> > challenge of seeing Pluto, there are reports of it being seen from
> > higher altitudes (over 4000 ft elevation) with apertures in the 70mm to
> > 90mm range.
>
> At the lower end of that range, you're now talking about the ability to
> see magnitude 8.7 with the naked eye.
And why not? Artificial stars have been seen in the laboratory (ie: a
fully darkened room with the observer in full dark adaptation) which are
as faint as magnitude 8.5 (See AMATEUR ASTRONOMER'S HANDBOOK by J. B.
Sidgwick, p. 26). Also, I said there were "reports" in the "range" of
70mm to 90mm, and not that I had seen it with such apertures. I have
not
succeeded with seeing Pluto at 80mm, but I have at 94mm (I have a 6mm
measured pupil diameter when fully dilated). Others with better eyes
might do slightly better.
> Point sources are not the same as extended objects.
No one SAID they were. However, it is a well known fact that increasing
the power TO A CERTAIN DEGREE can help improve the visiblity of fainter
stars in the telescope. If you are unaware of this, then you clearly
have not been observing enough with the eye and an amateur-class
telescope.
This improvement also applies to detail in some deep-sky objects where
increased scale and reduced competing skyglow are both needed. The
optimum
magnification for objects near the limits of vision is also discussed on
page 2 of HANDBOOK AND CATALOG OF DEEP-SKY OBJECTS, by C. B. Luginbuhl
and
B. Skiff., and that "limit" is surprisingly high.
> > I first saw Pluto in an 8 inch in the mid 1970's after I
> > had learned to kick up the power slightly to make it stand out somewhat
> > better.
>
> How can you be sure that you really saw it as opposed to having imagined
> that you saw it?
Oh, I am QUITE sure, because in April of 1974:
1. I located the correct field in my old 8 inch f/7 Newtonian using
charts published for the Pluto yearly track field (Sky and Telescope)
for mid-April of 1974 when Pluto was in Coma Berenices near the
magnitude 7.9 star SA0 100258. The nights I made the observations
were clear with no moon, and under dark sky conditions (ZLM 6.9)
2. I sketched the field at 120x, and for three evenings (April 13th,
15th,and 17th, 1974 at about 0400 UTC), noted the stars in the field
which were visible.
3. Pluto was visual magnitude 13.8 at the time.
4. One of the stars sketched on April 13th a little east of the mag.
7.9 star was not seen at that location on April 15th or the 17th, but a
"new" one was visible west of the star on the 17th. In other words:
something had moved, and that something was Pluto.
Since most amateurs did not possess highly detailed atlases which went
to faint magnitudes in 1974 (Atlas Coeli stopped at 7.75), this was the
method most amateurs used at the time to verify that they had seen
Pluto.
I went back to one of my old logbooks and found the original sketch. I
looked up the field using MEGASTAR, and several stars were shown on my
drawing which were fainter than 14th magnitude, including one which was
14.6.
The drawn locations for Pluto on the sketch were reasonably consistent
with the computer's plotted positions for the dates in question to be
certain
that the 1974 attempt had indeed succeeded. The non-visiblilty of Pluto
on
April 15th was probably due to it being too close to the magnitude 7.9
star
SAO 100258 to be easily seen at only 120x (21.2 arc seconds to the
north-
northwest of the star at 0400 on the 15th).
Now that I have computer atlases like MEGASTAR, I can get enough stars
plotted and identified to make spotting Pluto on a single evening alone
to be reasonably successful in my ten inch, provided it isn't too close
to another brighter star and moderate power is used (141x and 220x will
both show it). I found Pluto this way using an Meade 8 inch LX-200
Schmidt-Cassegrain a few years ago while helping a friend at the
Nebraska Star Party with his attempt to image the planet for a
multi-night sequence (unaided eye ZLM 8.0). At that time, it was not
all that much more difficult to see than it had been in the ten inch.
One evening a couple of years ago, I located Pluto with my ten inch at
full aperture from my rural observing site 15 miles east of my home (a
site with a typical ZLM of from 6.5 to 7.2), and then put on my
off-axis variable aperture stop. At its widest opening (94mm), Pluto
was still barely visible, although from its faintness, I doubt that
I could ever consistently see it at a smaller aperture (it was not
visible using the 80mm stop). One telling comment appears in the
2000 R.A.S.C. OBSERVER'S HANDBOOK in the section on Pluto; "A few
observers (with good optics, transparent skies and high
magnifications) succeeded in sighting Pluto with telescopes as small
as 100 mm refractors." It seems that I am far from alone when it
comes to picking up the planet with a less than massive aperture.
This will not be the case in a few decades when Pluto is more
distant, but it is now, and will be for a few more years.
tho...@antispam.ham
> [attribution not retained by above author]
>> It is the opinion of this author that, in light of the evidence
>> already obtained through the use of the Pioneer 10 and
>> 11 and two Voyager space craft, the Infrared Imaging
>> Satellite (IRAS, `83-84) and the data available to Harrington
>> when consulting with Sitchin that the search has already
>> been accomplished, in fact that the planet has already
>> been found. It is interesting that Harrington dispatched an
>> appropriate telescope to Black Birch, New Zealand to
>> get a visual confirmation, based on the data leading to
>> the expectation that it would be below the ecliptic in the
>> southern skies at this point in its orbit. On Harrington's
>> early death the scope was immediately called back - as one
>> observer noted, "almost before he was cold". ...
> Anyone of the "big fish" want to comment on this?
Who are "big fish"?
> Tholen, Knisely, Neill, Schlyter?
No such planet has already been found.
> maybe Van Flandern, Neugebauer, Scotti or others care to comment
> on the occupational hazards of astronomy :O
Domes are dark when working. Easy to bump your head on a mount
component.
tho...@antispam.ham
>>> As for the challenge of seeing Pluto, there are reports of it being seen
>>> from higher altitudes (over 4000 ft elevation) with apertures in the 70mm
>>> to 90mm range.
>> At the lower end of that range, you're now talking about the ability to
>> see magnitude 8.7 with the naked eye.
> And why not?
Who said anything about "not"? I've consistently avoided making any
claims about what is and what is not humanly possible, because I know
that not all eyes are alike. However, the greater the departure from
the norm, the lesser the probability. Perhaps you've heard the phrase
that extraordinary claims require extraordinary proof.
> Artificial stars have been seen in the laboratory (ie: a
> fully darkened room with the observer in full dark adaptation) which are
> as faint as magnitude 8.5 (See AMATEUR ASTRONOMER'S HANDBOOK by J. B.
> Sidgwick, p. 26).
Still not as faint as 8.7. And how was it determined that such artificial
stars were really seen, as opposed to imagined?
> Also, I said there were "reports" in the "range" of 70mm to 90mm, and
> not that I had seen it with such apertures.
I'm well aware of what you said. My response included nothing to
indicate any lack of such awareness.
> I have not succeeded with seeing Pluto at 80mm, but I have at 94mm (I
> have a 6mm measured pupil diameter when fully dilated). Others with
> better eyes might do slightly better.
Or they might imagine seeing something.
>> Point sources are not the same as extended objects.
> No one SAID they were.
So why did you delete the context? The discussion has been about the
detectability of Pluto, a point source, and you posted:
DK] This technique has served me well for viewing things like
DK] fainter detail in some smaller spiral galaxies. I often use powers from
DK] about 10x per inch to 15x per inch of aperture on galaxies and have
DK] found the additional magnification to be quite beneficial in revealing
DK] some additional detail. There are some galaxies which will stand even
DK] more power (220x to 253x with my ten inch Newtonian), so the tired old
DK] adage of staying with "low power" to view galaxies isn't entirely
DK] accurate under all conditions.
So, was the above a mere irrelevance?
> However, it is a well known fact that increasing the power TO A CERTAIN
> DEGREE can help improve the visiblity of fainter stars in the telescope.
I'm still waiting for an explanation for the alleged phenomenon.
> If you are unaware of this, then you clearly have not been observing
> enough with the eye and an amateur-class telescope.
Oh, so now the magnification matters only in amateur-class telescopes!
The phenomenon doesn't work on professional telescopes? For the
records, I've made THOUSANDS of photometric observations that involved
the centering of a faint source in the aperture of a photoelectric
photometer. I'm very familiar with the limiting magnitude of
telescopes ranging up to 2.3 meters (though I've used even larger ones,
they didn't have eyepieces attached to them), and there was plenty of
magnification involved.
> This improvement also applies to detail in some deep-sky objects where
> increased scale and reduced competing skyglow are both needed. The
> optimum magnification for objects near the limits of vision is also
> discussed on page 2 of HANDBOOK AND CATALOG OF DEEP-SKY OBJECTS, by
> C. B. Luginbuhl and B. Skiff., and that "limit" is surprisingly high.
Point sources are not the same as extended objects.
>>> I first saw Pluto in an 8 inch in the mid 1970's after I
>>> had learned to kick up the power slightly to make it stand out somewhat
>>> better.
>> How can you be sure that you really saw it as opposed to having imagined
>> that you saw it?
> Oh, I am QUITE sure, because in April of 1974:
>
> 1. I located the correct field in my old 8 inch f/7 Newtonian using
> charts published for the Pluto yearly track field (Sky and Telescope)
> for mid-April of 1974 when Pluto was in Coma Berenices near the
> magnitude 7.9 star SA0 100258. The nights I made the observations
> were clear with no moon, and under dark sky conditions (ZLM 6.9)
Using charts! Hardly a blind test (an admittedly ironic name for such
a test in this case).
> 2. I sketched the field at 120x, and for three evenings (April 13th,
> 15th,and 17th, 1974 at about 0400 UTC), noted the stars in the field
> which were visible.
>
> 3. Pluto was visual magnitude 13.8 at the time.
At which time? I estimate that Pluto was 13.94 on April 13, 14.16 on
April 15, and 14.00 on April 17. You see, it has a rotational lightcurve
that modulates the brightness over a 6.3872 day interval.
> 4. One of the stars sketched on April 13th a little east of the mag.
> 7.9 star was not seen at that location on April 15th or the 17th, but a
> "new" one was visible west of the star on the 17th. In other words:
> something had moved, and that something was Pluto.
With knowledge that it should have moved from one side of the star to
another, per your charts. That's not a blind test.
However, that's for an 8 inch, not a 3.7 inch.
> Since most amateurs did not possess highly detailed atlases which went
> to faint magnitudes in 1974 (Atlas Coeli stopped at 7.75), this was the
> method most amateurs used at the time to verify that they had seen
> Pluto.
> I went back to one of my old logbooks and found the original sketch. I
> looked up the field using MEGASTAR, and several stars were shown on my
> drawing which were fainter than 14th magnitude, including one which was
> 14.6.
> The drawn locations for Pluto on the sketch were reasonably consistent
> with the computer's plotted positions for the dates in question to be
> certain that the 1974 attempt had indeed succeeded. The non-visiblilty
> of Pluto on April 15th was probably due to it being too close to the
> magnitude 7.9 star SAO 100258 to be easily seen at only 120x (21.2 arc
> seconds to the north-northwest of the star at 0400 on the 15th).
And am I supposed to be impressed that you saw Pluto in an 8-inch? That
corresponds to magnitude 6.2 with the naked eye. Not uncommon.
> Now that I have computer atlases like MEGASTAR, I can get enough stars
> plotted and identified to make spotting Pluto on a single evening alone
> to be reasonably successful in my ten inch, provided it isn't too close
> to another brighter star and moderate power is used (141x and 220x will
> both show it). I found Pluto this way using an Meade 8 inch LX-200
> Schmidt-Cassegrain a few years ago while helping a friend at the
> Nebraska Star Party with his attempt to image the planet for a
> multi-night sequence (unaided eye ZLM 8.0). At that time, it was not
> all that much more difficult to see than it had been in the ten inch.
> One evening a couple of years ago, I located Pluto with my ten inch at
> full aperture from my rural observing site 15 miles east of my home (a
> site with a typical ZLM of from 6.5 to 7.2),
8 inches and 10 inches are not 3.7 inches.
> and then put on my off-axis variable aperture stop. At its widest
> opening (94mm), Pluto was still barely visible,
How can you be sure it wasn't your imagination?
> although from its faintness, I doubt that
> I could ever consistently see it at a smaller aperture (it was not
> visible using the 80mm stop). One telling comment appears in the
> 2000 R.A.S.C. OBSERVER'S HANDBOOK in the section on Pluto; "A few
> observers (with good optics, transparent skies and high
> magnifications) succeeded in sighting Pluto with telescopes as small
> as 100 mm refractors."
That's 4 inches. Apparently they don't know about your 3.7 inch feat.
> It seems that I am far from alone when it
> comes to picking up the planet with a less than massive aperture.
Lots of people could imagine seeing it.
> This will not be the case in a few decades when Pluto is more
> distant, but it is now, and will be for a few more years.
Irrelevant to the issue.
So, whatever happened to the "PLONK"?
da...@pebble.org
<tho...@AntiSpam.ham> wrote:
> Domes are dark when working. Easy to bump your head on a mount
> component.
I have several lumps on my head to prove it. I've also stubbed my
toes a few times. Ouch. :-(
- Dan
David W Knisely
> At which time? I estimate that Pluto was 13.94 on April 13, 14.16 on
> April 15, and 14.00 on April 17. You see, it has a rotational lightcurve
> that modulates the brightness over a 6.3872 day interval.
It was 13.9 (typo) in April of 1974 (13.8 now). However, the precise
magnitude is still irrelevant, as even mag. 14 stars are still within
the range of a good 8 inch under good conditions (a 14.5 to 15th mag.
limit for an 8 inch is fairly common, depending on conditions and the
observer). A variation of a tenth of a magnitude for viewing Pluto in
an 8 inch still doesn't amount to a hill of beans.
> And am I supposed to be impressed that you saw Pluto in an 8-inch? That
> corresponds to magnitude 6.2 with the naked eye. Not uncommon.
>
No, being "impressed" was not required (or expected). However, you did
unfairly challenge my claim of seeing Pluto in the mid 1970's with an 8
inch. Right after you quoted my comment about when I first saw Pluto,
you said, "How can you be sure that you really saw it as opposed to
having imagined that you saw it?". You didn't refer to the 3.7 inch
observation when you wrote that. You are still quite wrong, as I DID
see Pluto then (and have seen it several times since then). You have NO
evidence to the contrary, yet you continue to challenge this. You do a
nice "dance" back and forth, sniping at this or challenging that in your
own condescending way, but in the long run, the criticism just doesn't
hold much water. You blather forth arguments for mere argument's sake,
and not for conducting a useful discussion. This is rather childish and
unethical.
> > 2000 R.A.S.C. OBSERVER'S HANDBOOK in the section on Pluto; "A few
> > observers (with good optics, transparent skies and high
> > magnifications) succeeded in sighting Pluto with telescopes as small
> > as 100 mm refractors."
>
> That's 4 inches. Apparently they don't know about your 3.7 inch feat.
>
Wrong. Its about 3.94 inches. The difference in magnitude for a 3.94
inch to a 3.70 inch aperture is only about 0.11 magnitudes, which isn't
a large enough difference to necessarily invalidate a claim of a
sighting with a 3.7 inch outright. As I stated, I did not see Pluto in
an 80mm aperture, but did detect it at 94 mm aperture (a difference in
limiting magnitude of 0.35 magnitudes, which *is* significant).
Considering how faint Pluto was at the 94mm aperture level, that appears
to be *my* faint limit for Pluto at mag. 13.8.
> 8 inches and 10 inches are not 3.7 inches.
Oh, so *NOW* you are giving me credit for actually SEEING Pluto in an 8
inch? How "kind" of you.
I was rather skeptical of the possiblity of Pluto being viewed in
anything less than a six inch. I only did the 3.7 inch "test" to see
for myself when I read accounts from others of viewing Pluto in a 100 mm
refractor on one of the lists I subscribe to. When I was able to just
barely see it in the 3.7 inch stop under very good conditions, I
conceeded that 100 mm would be possible. I remain somewhat skeptical
about Pluto sighting claims using less than 90 mm of aperture, but am
aware that some eyes might be able to go fainter than mine, so I won't
absolutely rule it out.
> > If you are unaware of this, then you clearly have not been observing
> > enough with the eye and an amateur-class telescope.
>
> Oh, so now the magnification matters only in amateur-class telescopes!
> The phenomenon doesn't work on professional telescopes? For the
> records, I've made THOUSANDS of photometric observations that involved
> the centering of a faint source in the aperture of a photoelectric
> photometer. I'm very familiar with the limiting magnitude of
> telescopes ranging up to 2.3 meters (though I've used even larger ones,
> they didn't have eyepieces attached to them), and there was plenty of
> magnification involved.
So, now am I supposed to be impressed? Hardly! Those eyepieces
probably yielded more power than the modest increase in magnification
necessary to improve the visibility of faint stars. In short, you were
already "there". You keep missing the point. You also weren't trying
to see Pluto in a modest aperture telescope where its faintness relative
to the sky background seen at very low power might be a problem.
Increasing the power over the lowest magnification possible does help
dilute the weak skyglow and improve the contrast between the stars and
the background, although going too high will, of course, start to negate
that gain. There may also be some slight physiological effect in the
way the retina perceives a faint point source impacting only on a
portion of one or two cells verses a faint source slightly enlarged
which is more fully illuminating the cells. Whatever the reason, the
observational fact is that if a person wants to push their telescope to
its limiting magnitude, it is best not to use the lowest possible powers
(ie: 3.6x to 6.4x per inch of aperture), but to increase the power
somewhat (10x to 17x per inch or so).
> How can you be sure it wasn't your imagination?
Oh brother, are you ever caught in a rut! I either see something or I
don't.
> > It seems that I am far from alone when it
> > comes to picking up the planet with a less than massive aperture.
>
> Lots of people could imagine seeing it.
>
> > This will not be the case in a few decades when Pluto is more
> > distant, but it is now, and will be for a few more years.
>
> Irrelevant to the issue.
Gad, you still won't quit! No wonder the N***y troll finds you so
attractive!
> So, whatever happened to the "PLONK"?
I'm sorry I ever deactivated it.............................PLONK!
tho...@antispam.ham
>> At which time? I estimate that Pluto was 13.94 on April 13, 14.16 on
>> April 15, and 14.00 on April 17. You see, it has a rotational lightcurve
>> that modulates the brightness over a 6.3872 day interval.
> It was 13.9 (typo) in April of 1974 (13.8 now).
I just finished telling you that the brightness is modulated over a
6.3872 day period. That means it went through about five cycles in
April of 1974, so you can't simply say it was 13.9 in April of 1974.
> However, the precise magnitude is still irrelevant, as even mag. 14 stars
> are still within the range of a good 8 inch under good conditions (a 14.5
> to 15th mag. limit for an 8 inch is fairly common, depending on conditions
> and the observer).
An 8-inch is not a 3.7-inch.
> A variation of a tenth of a magnitude for viewing Pluto in an 8 inch still
> doesn't amount to a hill of beans.
Incorrect; it amounts to a tenth of a magnitude. However, you should be
aware that Pluto's lightcurve variation is currently around 0.3 mag, and
the lightcurve maximum is fairly brief.
>> And am I supposed to be impressed that you saw Pluto in an 8-inch? That
>> corresponds to magnitude 6.2 with the naked eye. Not uncommon.
> No, being "impressed" was not required (or expected). However, you did
> unfairly challenge my claim of seeing Pluto in the mid 1970's with an 8
> inch.
On the contrary, I haven't challenged any such claim. Did you bother to read
what I wrote? You removed the relevant text. Let me restore it for you:
DT] I've consistently avoided making any claims about what is and what is
DT] not humanly possible, because I know that not all eyes are alike.
DT] However, the greater the departure from the norm, the lesser the
DT] probability. Perhaps you've heard the phrase that extraordinary
DT] claims require extraordinary proof.
The extraordinary claim in this case was your claim that you saw Pluto
through a 3.7-inch telescope. Why do you think I keep noting that an
8-inch isn't a 3.7-inch? Seeing Pluto through an 8-inch isn't an
extraordinary claim; why do you think I wrote "Not uncommon"?
> Right after you quoted my comment about when I first saw Pluto,
> you said, "How can you be sure that you really saw it as opposed to
> having imagined that you saw it?".
In reality, my first response to you regarding the visibility of Pluto
is reproduced here for your convenience:
] David W Knisely writes:
]
] > Well, under good seeing conditions and under a fairly dark sky, Pluto
] > can be seen in a scope smaller than 8 inches. I have seen it (barely)
] > using only a 3.7 inch aperture,
]
] Which means you should be able to see magnitude 8 stars with a dark
] adapted naked eye.
> You didn't refer to the 3.7 inch observation when you wrote that.
You did refer to the 3.7-inch in the message to which my first response
was written.
> You are still quite wrong,
What am I allegedly wrong about?
> as I DID see Pluto then
I never said you didn't see Pluto then, therefore I cannot be wrong.
Of course, I never confirmed that you did see Pluto then either. I
simply noted that such a feat implies an ability to see magnitude 8
stars with the naked eye. The relevant evidence is reproduced above.
> (and have seen it several times since then).
Irrelevant to the claim that you saw Pluto through a 3.7-inch. I've
also seen Pluto several times since then. Several hundred, in fact.
> You have NO evidence to the contrary,
You made the claim, therefore the burden of proof falls on your
shoulders. If you expect me to simply accept your word, then why
not expect others to simply accept Nancy's word? As I said,
extraordinary claims call for extraordinary proof. I'm still
waiting for yours. Simply claiming that you DID see Pluto then
is no better than what Nancy is doing with her claims.
> yet you continue to challenge this.
See above for why.
> You do a nice "dance" back and forth, sniping at this or challenging
> that in your own condescending way,
How ironic, coming from someone who chose to introduce my text as
written by a "sad person", a "sad and bitter person", and as "Tholen
person". You really should pay some attention to your own back and
forth "dance", accompanied by your own condescending way.
> but in the long run, the criticism just doesn't hold much water.
On the contrary, until extraordinary proof is provided for an
extraordinary claim, the criticism is quite valid.
> You blather forth arguments for mere argument's sake,
Balderdash. You're now attaching colorful language like "blather"
to try and weaken my argument.
> and not for conducting a useful discussion.
How ironic, coming from someone who is now arguing about the style
of argument, rather than concentrating on the issue at hand, namely
the extraordinary proof for an extraordinary claim.
> This is rather childish and unethical.
And rather hypocritical of you.
>>> 2000 R.A.S.C. OBSERVER'S HANDBOOK in the section on Pluto; "A few
>>> observers (with good optics, transparent skies and high
>>> magnifications) succeeded in sighting Pluto with telescopes as small
>>> as 100 mm refractors."
>> That's 4 inches. Apparently they don't know about your 3.7 inch feat.
> Wrong. Its about 3.94 inches.
Which rounds to 4 inches. Please note the level of precision to which
the number is given.
> The difference in magnitude for a 3.94 inch to a 3.70 inch aperture is
> only about 0.11 magnitudes,
Depending on magnification, according to you.
> which isn't a large enough difference to necessarily invalidate a claim
> of a sighting with a 3.7 inch outright.
Who said anything about invalidation? Looks like you need another
refresher:
DT] I've consistently avoided making any claims about what is and what is
DT] not humanly possible, because I know that not all eyes are alike.
DT] However, the greater the departure from the norm, the lesser the
DT] probability. Perhaps you've heard the phrase that extraordinary
DT] claims require extraordinary proof.
> As I stated, I did not see Pluto in an 80mm aperture, but did detect it
> at 94 mm aperture (a difference in limiting magnitude of 0.35 magnitudes,
> which *is* significant).
About the size of the lightcurve variation for Pluto. Of course, that
variation amounted to "a hill of beans" previously.
> Considering how faint Pluto was at the 94mm aperture level, that appears
> to be *my* faint limit for Pluto at mag. 13.8.
It appears that you didn't even know the correct magnitude for Pluto at
the times of the observations.
>> 8 inches and 10 inches are not 3.7 inches.
> Oh, so *NOW* you are giving me credit for actually SEEING Pluto in an 8
> inch?
Apparently you're still having trouble comprehending what I've previously
written. Let me refresh your memory yet again:
DT] And am I supposed to be impressed that you saw Pluto in an 8-inch?
DT] That corresponds to magnitude 6.2 with the naked eye. Not uncommon.
> How "kind" of you.
How ironic, coming from someone whose "kindness" consists of "sad
person", "sad and bitter person", and "Tholen person".
> I was rather skeptical of the possiblity of Pluto being viewed in
> anything less than a six inch.
And yet you won't accept the skepticism of someone evaluating the claim
that Pluto was seen in a 3.7-inch? You're aware of your own skepticism
and can't imagine someone else having skepticism over an even less likely
scenario? Amazing!
> I only did the 3.7 inch "test" to see for myself when I read accounts
> from others of viewing Pluto in a 100 mm refractor on one of the lists
> I subscribe to.
But it wasn't a blind test. So just how can you be sure? I keep asking
you this, but you keep avoiding it.
> When I was able to just barely see it in the 3.7 inch stop under very
> good conditions, I conceeded that 100 mm would be possible.
If you can imagine seeing it, someone else can imagine seeing it as well.
> I remain somewhat skeptical about Pluto sighting claims using less than
> 90 mm of aperture,
And yet you won't accept the skepticism of someone evaluating the claim
that Pluto was seen in a 3.7-inch? You're aware of your own skepticism
and can't imagine someone else having skepticism over an even less likely
scenario!
> but am aware that some eyes might be able to go fainter than mine, so I
> won't absolutely rule it out.
Gosh, doesn't that sound familiar:
DT] I've consistently avoided making any claims about what is and what is
DT] not humanly possible, because I know that not all eyes are alike.
DT] However, the greater the departure from the norm, the lesser the
DT] probability. Perhaps you've heard the phrase that extraordinary
DT] claims require extraordinary proof.
>>> If you are unaware of this, then you clearly have not been observing
>>> enough with the eye and an amateur-class telescope.
>> Oh, so now the magnification matters only in amateur-class telescopes!
>> The phenomenon doesn't work on professional telescopes? For the
>> records, I've made THOUSANDS of photometric observations that involved
>> the centering of a faint source in the aperture of a photoelectric
>> photometer. I'm very familiar with the limiting magnitude of
>> telescopes ranging up to 2.3 meters (though I've used even larger ones,
>> they didn't have eyepieces attached to them), and there was plenty of
>> magnification involved.
> So, now am I supposed to be impressed?
You're supposed to be informed, considering your "if you are unaware of
this" remark.
> Hardly! Those eyepieces probably yielded more power than the modest
> increase in magnification necessary to improve the visibility of faint
> stars.
Ah, so now magnification hurts if it's too much? Perhaps you'd like to
present a plot of magnitude gain as a function of magnification. Note
that I purposely didn't state the magnification I used.
> In short, you were already "there". You keep missing the point.
On the contrary, I'm well aware of your point that magnification
allegedly improves the threshold of detection. What makes you think
otherwise?
> You also weren't trying to see Pluto in a modest aperture telescope
> where its faintness relative to the sky background seen at very low
> power might be a problem.
I was trying to see something even fainter than Pluto, something even
fainter relative to the sky background.
> Increasing the power over the lowest magnification possible does help
> dilute the weak skyglow and improve the contrast between the stars and
> the background, although going too high will, of course, start to negate
> that gain.
Why?
> There may also be some slight physiological effect in the way the
> retina perceives a faint point source impacting only on a portion
> of one or two cells verses a faint source slightly enlarged which
> is more fully illuminating the cells.
The key word here is "may". There "may" also be the effect of the
imagination.
> Whatever the reason, the observational fact is that if a person wants
> to push their telescope to its limiting magnitude, it is best not to
> use the lowest possible powers (ie: 3.6x to 6.4x per inch of aperture),
> but to increase the power somewhat (10x to 17x per inch or so).
Is that supposed to support the claim that you saw Pluto in a 3.7-inch
telescope?
>> How can you be sure it wasn't your imagination?
> Oh brother, are you ever caught in a rut!
I'm still waiting for an answer.
> I either see something or I don't.
Are you claiming that it is not possible to imagine seeing something?
What happens if a cosmic ray hits your retina?
>>> It seems that I am far from alone when it
>>> comes to picking up the planet with a less than massive aperture.
>> Lots of people could imagine seeing it.
>>> This will not be the case in a few decades when Pluto is more
>>> distant, but it is now, and will be for a few more years.
>> Irrelevant to the issue.
> Gad, you still won't quit!
How ironic, coming from the person who still won't quit, even after
posting a PLONK with such fanfare (but no corresponding UN-PLONK;
interesting inconsistency).
> No wonder the N***y troll finds you so attractive!
Right now you're the one finding me so "attractive".
>> So, whatever happened to the "PLONK"?
> I'm sorry I ever deactivated it.............................PLONK!
Famous last words. It meant nothing last time. Why should I believe
it means anything this time? Your "back and forth dance" is rather
ironic, considering your remarks above.
Michael Edelman
>
>.... Pluto is reflecting sunlight, Planet X
> does not but has its own diffuse glow....
It's so sad when cousins marry.
-- mike
---------------------------------------------------------------
Michael Edelman m...@spamcop.net
The Small Kahuna
Yes, it is, Mike, are your parents first or second cousins? A true sign
of intelligence is the ability to communicate, in spite of subtle and
irrelevant differences in word usage. Its always amazing how the Really
Good Professors are also able to somehow explain Deep Things to
"ordinary" people. These ordinary people cannot do the advanced math,
but they walk away with some kind of internalization of what the person
is explaining - they get the point. Sadly, the reverse is not often
true where a scientist/engineer or other "educated" individual is able
to take someone seriously in spite of a difficulty with the lingo or a
poor command of math.
So let me try and put some "technical lingo" around the above.
The spectrum of light from pluto is the summation of the inherent glow
of the object and the convolution of the albedo spectrum with the
incident spectrum. (Since you probably slept through Calculus, the
convolution is the point by point multiplication of two functions in the
frequency domain, and in this case frequency is "color". In other words
if you shine a white light on a red object, it looks red and if you
shine a red light on a blue object it looks black or deep brown, the
color coming from the incident light as filtered by the illuminated
object.)
Now pluto will glow with what is essentially a black body spectrum, but
the surface of the planet is very cold because it does not either have
any significant self heating nor does it receive sufficient energy from
the sun to warm up. As a first order approximation, the black body
spectrum can be ignored because it is so deep in the infrared that you
need very specialized and super cooled equipment to measure it.
The Sun is a black body radiator something around 6600K with spectral
lines from excited ions in the outer layers of the surface and
absorption lines from other layers. It is black body but kind of
"noisy". This radiation eventually reaches Pluto and so the planet
could be said to "shine" because it reflects the sunlight according to
its albedo function and according to the incident radiation. Since we
already agreed that the black body radiation from Pluto is
insignificant, the primary radiation we see is (more or less) visible
light from the sun.
Now the amount of energy that reaches a specific point from the sun
follows an inverse square law. Twice as far gives only 1/4 of the
light, and so on.
This object (Planet X) is being described as a "smoldering brown dwarf",
and before we start arguing about what that actually mean, lets agree
that the description is not relevant, only its spectrum is. If it is
what it is claimed to be, this object will have a more complex spectrum
than one is used to.
First it will be a black body radiator of something around 300K plus or
minus. While this is much "hotter" than Pluto, it is still something
that will require specialized equipment to measure. So, again, we will
ignore its black body radiation.
In addition it has an albedo function as well and so will reflect
sunlight. After all, it *has* to, unless it is a black hole. However,
since it is also stated that it is approximately 9 times further than
Pluto right now, it will be 81 times dimmer. (1/9^2) Because the
reflected light is so much dimmer, we will also ignore it too.
This leaves the other self radiation of the object, which is described
as some kind of chemical reaction. Whether it really is or not, is not
relevant, only that it is radiating, it is not strictly black body, so
it probably has a very spiky spectrum related to the causal mechanism,
kind of like if you look at a "white" fluorescent lamp through a
spectrum analyzer. (I made one from a used razor blade, a plastic
diffraction grating, a cardboard box, and duct tape as a college physics
lab once.)
So in other words, what you will be able to actually SEE is not the
black body radiation or the reflected light, but its self illumination
because it swamps out everything else - just like she said:
>Nancy Lieder wrote:
>>
>>.... Pluto is reflecting sunlight, Planet X
>> does not but has its own diffuse glow....
only without all the blather about black bodies, convolution and
absorption lines.
By analogy, you are standing outside your house in the pitch dark, a few
feet from a street lamp. A mile down the road is an oncoming car with
it's parking lights on. What color is the car? You will have to wait
until it gets much closer to the street lamp to be able to tell.
The bottom line is what the readers of this news group are being
challenged to do is the following:
1) Take a long exposure (hopefully black and white) CCD picture of the
supplied coordinates with enough magnification to resolve details.
2) Contrast invert the picture (as a convenience to the viewer).
3) Post the image on the news group (not the *.gif, the image - a gif
file will introduce compression artifacts).
4) Point to the supplied coordinates and say "see, Nancy, there is
nothing there!"
5) Wait a month.
6) Repeat steps 1-4.
7) Subtract this image from last month's image and look for differences
around the supplied target area.
8) Post the difference image.
9) repeat steps 1-8 for several months
10) gloat because there is nothing there but noise
-or-
10) Notice that, sure enough, there is this fuzzy thing, and it is
moving (more or less) in the direction and track being described. It is
not *exactly* at the coordinates Nancy provided, but it is Real Close.
And it is *moving*.
11) Suck wind because *you* don't have an explanation.
I mean, really, how hard could the above be for some of the more well
heeled amateurs out there (with the larger 'scopes, tracking mounts and
CCD cameras - especially if it is cooled with a Peltier)? It might
actually be fun, with the additional carrot at the end of the stick that
you get to be really superior, insulting and obnoxious at the end, and
you will have DATA to prove it. Yep! DATA, the difference between a
student and a professor...
So, Mike, what do you say? Can you convince your cousin - er - wife to
let you outside long enough to take this picture?
BAAAAAHH
Chosp
"The Small Kahuna" <per...@company.com> wrote in message
news:3B0DA38B...@company.com...
> In addition it has an albedo function as well and so will reflect
> sunlight. After all, it *has* to, unless it is a black hole. However,
> since it is also stated that it is approximately 9 times further than
> Pluto right now, it will be 81 times dimmer. (1/9^2) Because the
> reflected light is so much dimmer, we will also ignore it too.
Why do you not include the fact that she said it was visible as a
2nd magnitude object which changed to 11th magnitude as it
came closer?
> BAAAAAHH
You should do something about that cough.
Nancy Lieder
wrote:
> In Article <3B0DA38B...@company.com>The Small Kahuna wrote:
>> However, since it is also stated that it is approximately
>> 9 times further than Pluto right now, it will be 81 times
>> dimmer. (1/9^2) Because the reflected light is so much
>> dimmer, we will also ignore it too.
>
> Why do you not include the fact that she said it was visible
> as a 2nd magnitude object which changed to 11th magnitude
> as it came closer?
Why is it you fail to register the difference between ABSOLUTE and
APPARENT magnitude?
In Article <3mdL6.16929$g61.1...@e420r-chi1.usenetserver.com> S.
Welknelk wrote:
> In article <cAvK6.2476$n81.1...@typhoon.hawaii.rr.com> Dave Tholen
wrote:
>> The object cannot be both 2nd magnitude and 11th magnitude.
>
> Why all the BS about the difference between ABSOLUTE magnitude
> and APPARENT magnitude? Our own sun has an ABSOLUTE
> magnitude of +4.85 (if viewed from 10 parsecs distance from
> earth, standard definition). Isn't the APPARENT magnitude,
> even on a cloudy day, something brighter than +4.85? Unless
> you were looking for the sun at midnight I suppose, which
> could not be discounted based on the moronic replies I have
> seen here.
-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
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tho...@antispam.ham
> Chosp wrote:
>> The Small Kahuna wrote:
>>> However, since it is also stated that it is approximately
>>> 9 times further than Pluto right now, it will be 81 times
>>> dimmer. (1/9^2) Because the reflected light is so much
>>> dimmer, we will also ignore it too.
>> Why do you not include the fact that she said it was visible
>> as a 2nd magnitude object which changed to 11th magnitude
>> as it came closer?
> Why is it you fail to register the difference between ABSOLUTE and
> APPARENT magnitude?
Probably because you failed to register that difference. He's
just going on the basis of what you said. Where have you ever
specified that difference? Care to tell us what the absolute
magnitude allegedly is, as well as how it's defined?
Magnus Nyborg
<tho...@AntiSpam.ham> wrote in message
news:nlON6.3635$WI.10...@typhoon.hawaii.rr.com...
> Magnus Nyborg writes:
>
[...]
> > Stars are for all practical purposes pinpoints up to magnification of
about
> > 150x in a 12" at my location on most nights.
>
> What are "practical purposes" in the context of this discussion?
When observing visually, for "practical reasons" means that you cannot
distinguish between a true pinpoint, and a star.
[...]
>
> > Does the camcorder have auto-dark set for the background ?
>
> No.
>
> > Don't compare a camcorder with an eye, there is no comparison.
>
> In the case of magnification enhancing detectability, one can make a
> comparison, and in this case, the camcorder performed in a way that
> you've been claiming for the eye.
>
> > They don't work the same !
>
> Irrelevant, given that I didn't say they do.
Irrelevant since I claim they don't !
[...]
> > Siliness! If the model is incorrect, it does not matter if you think it
is
> > selfreferential ! Being selfreferential is not a guarantee for
> > correctness...
>
> It is a guarantee for circular reasoning in this case.
...and if your reasoning is wrong, you will never escape the loop !!
[...]
> > Mainly since the smaller exit-pupil of the eyepiece reduces the
aberrations
> > induced by the eye's single (chromatic and spherical aberration) lens.
A
> > F/2 eye _must_ be much worse than an F/10 eye (not knowing the real
> > parameters here). The brain processes much of the chromatic and possibly
> > spherical aberrations out.
>
> And how does the convergence of the light cone affect transmission?
It doesn't, it creates a better focussed image, with a higher "Strehl" which
results in a brighter image!
Since this is basic optical theory, I have to assume that you don't really
know aboput these things!
>
> >>> 2. The eye is not a linear device, and a larger magnification will
some
> >>> times (many times) improve the contrast against the background. A
linear
> >>> device can not do this.
>
> >> For objects that are truly point sources. But see above.
>
> > Not only for objects that are pinpoints, the effect is often referred to
> > while locating dim fuzzies...
>
> How does magnification improve contrast on "dim fuzzies"?
It shouldn't, according to the linear model, but it does, as real
observations show!
[...]
> > Yes, a real test takes a lot of preparations - would you like to carry
them
> > out.
>
> Sure, I'd be happy to. Would you like to fund them?
So, whe have a stalemate here - you refusing to learn, and me unable to
provide the funds!
>
> > If you don't, stop hiding behind a blanket of selfricheousness...
>
> I'm not hiding at all; I'm discussing the issue right here, out in the
> open. Furthermore, you're erroneously presupposing the existence of
> some "blanket of selfricheousness".
Citing a well known poster in this group "Dave Tholen is the junkyard dog of
sci.astro"...
It's not only me that believes this...
>
> > My observations are reported by others,
>
> Which by definition makes them second hand.
Correct! But does not make them untrue...
>
> > and I am experienced enough to avoid fooling myself about detecting a
> > star or something.
>
> Doesn't that mean you're sure one way or the other?
Given the statistical probability, you cannot be sure. Heard about sigma-2,
sigma-3, sigma-5 etc ??
>
> > If I have a 50/50 detection, I say soo...
>
> Which means you're not sure, which means you might be fooling yourself.
Which means that I if 1000 observers have a 50/50 detection, they
practically confirm eachothers observation. Heard about statistical
probability ??
>
> >>> Not having a scientificly explained model for the eye, this can not be
> >>> proven with mathematics, but clearly the eye can be proven to _not_ be
> >>> linear using a very simple test.
>
> >> That the eye is not a linear device is not the issue.
>
> > Ooh, but it is -
>
> On the contrary, the issue is detectability as a function of
magnification.
...which if true requires that the eye does not behave in a simplified
linear model. What part do you have problem understanding ?
>
> > you not understanding that it is,
>
> Balderdash; you can't pontificate about my alleged misunderstanding and
> use that to justify a change in the issue.
Perhaps it is time for you to ponder what "improved detection as a function
of magnification" actually implies.
>
> > does not change the fact
> > ! The eye being an non-linear device is what causes many of the observed
> > situations...
>
> The eye being non-linear is why the magnitude system is logarithmic.
> That doesn't prove that magnification enchances detectability.
The non-linearity we are talking about is whether detection is governed by
m0 + 5*log(D/d) or not. Using a linear model of the eye (as a functiona of
magnification) requires that m0 is held constant as magnification changes.
Now, do you believe that m0 is constant over a range of magnifications ?
>
> > A linear device would follow the formula m0 + 5*log( D / d) slavishly,
> > regardless of magnification.
>
> A non-linear device could also follow some formula slavishly, regardless
> of magnification.
It could...
>
> > The reported behaviour is _not_ following the formula,
>
> *Your* reported behavior does not follow the formula.
More people than me have this reported...
Yes, my report is also that the formula is not correct!
>
> > many contradictions reported,
>
> No sufficient explanation provided.
The linear model has been rejected by observations, although the
observations have not been carried out in a scientific manner. This cast's
doubt on the current interpretation, if not more...
Plausable explanations have been provided, although I realise that you have
not understood them.
>
> > QED: The linear formula is not correct!
>
> That doesn't logically follow. It has happened on many occasions that
> someone can get the right answer for the wrong reasons. You've personally
> observed a phenomenon; just because you've been able to come up with only
> one explanation for that phenomenon does not guarantee that your
> explanation is the correct one. See below for some other options.
I have only rejected the common explanation!
>
> > The behaviour is more that of an initially increasing m0 (from perhaps
6.5
> > to maybe 8.0) as magnification becomes larger and closes in on around
1mm
> > exit-pupil.
>
> What is special about 1 mm? Why not 0.5 mm? 0.1 mm?
Nothing special at all about 1mm, but it looks like the change comes to a
halt around 1mm...from observations it also seems that it may decrease with
even smaller exit-pupils, which would not be surprising.
>
> > [Disclaimer: Even if the behaviour of the eye is not linear, it can be
made
> > up of linear devices]
>
> Also irrelevant to the issue of magnification enhancing detectability.
Perhaps, and perhaps not! Given that I have not come up with the correct
explanation, only rejected the current explanation as insufficient, it is
impossible to really say...
>
> >>> Detection of faint objects can easily be shown to be improved when
using
> >>> higher magnificatiosn.
>
> >> Which is a restatement of the original claim for which I'm requesting
an
> >> explanation.
>
> > The evidence is only indicative, I have checked myself and talked to a
few
> > people, that's all.
>
> I have my own experience as well.
>
> > I know of no thourough study of this phenomenon,
>
> Yet you seem to be convinced of the One True explanation, namely
> magnification.
...since magnification changes many of the parameters of visual observation
(which by the way the unaided eye cannot) I would think that this should not
come as a surprise to you.
>
> > but many have reported what appears as confirmation.
>
> If one person can imagine seeing something below what is normally
considered
> the threshold of detectability, then it is reasonable to assume that
others
> could also imagine seeing something below what is normally considered the
> threshold of detectability. This discussion isn't too different from the
> ones involving speaker wire, for example. Can you hear a difference?
> Perhaps you've read about double-blind testing? Has it been done in this
> case?
>
> > Sorry, I am only one guy, as representative as I hope I am.
>
> And it's entirely possible for one guy to honestly claim that they saw
> Pluto through a 3.7-inch telescope without having actually seen it,
> given that the imagination can take over when working near thresholds,
> especially when they know something is supposed to be there.
>
> > My claims are that:
> > 1. The eye is not linear
>
> Irrelevant, given that I never said it isn't.
Relevant, since you claim that all reported phenomenon that does not follow
the linear formula is figments of imagination - I claim that the linear
model is incorrect...
>
> > 2. That m0 (in the formule m0 + 5*log(D / d) is dependant of
magnification
> > (which is the same as saying that the eye is not linear)
>
> On the contrary, those are substantially different claims. A detector
> can have non-linear response and still be independent of some effect.
Incorrect, a linear model of the eye, _results_ in the formula above...
>
> > and increases a little when going from a 7mm exit-pupil to a 1mm pupil.
>
> Can you explain that?
I have been doing that for some time now!
Why the eye behaves like this is up for interpretation, but that it does
behave like this seems both plausable and at least to some extent confirmed
by severl/many observers around the globe.
>
> > More factors than this have to be considered, like seeing, transparenty,
> > lightpollution etc,
>
> Not when the claim in question is restricted to magnification.
First take into account the effects above, then add the effect of
magnification. Transparency can of course not be neglected if you are going
to try detection of Pluto in a 3.7":er, or 6":er for that matter...
>
> > but what remains is a clear indication that m0 is
magnification-dependant.
>
> How can you be sure? To change magnification, you presumably changed the
> eyepiece. Maybe the shorter focal length eyepiece had fewer optical
> elements and transmitted more light. Maybe it had better antirelection
> coatings. Maybe it had a better design to correct for various kinds of
> aberrations. Yet for some reason, you're convinced that none of those
> are factors, and that it MUST be magnification.
You are assuming that I don't know what I am doing :o)
Since you obviously don't understand what I am talking about, and don't
intend to do, I can do nothing more...
>
> > Perhaps if you looked through your own scope and tested detecting dim
> > objects that you would become convinced that at least the linear model
for
> > the eye is not complete.
>
> I have, and I do not have any evidence to support the conclusion that
> magnification enhances detectability. I have not discussed any linear
> model for the eye. The eye, like the ear, is known to not be a linear
> detector. That's why stars visible to the naked eye range in brightness
> by about a factor of 100 (excluding the Sun) but were assigned magnitudes
> that range (historically) from about 1st to 6th magnitude.
A veeeery simple question - have you tried limit-detections of objects using
different magnifications ? If not, come back when you have !!
>
> >>> Just try to located an object close to the limits of
> >>> the telescope using
> >>> 1. 5 exit-pupil, and...
> >>> 2. 1 mm exit-pupil
> >>>
> >>> ....and compare the results.
>
> >> How about comparing the limiting magnitude for the naked eye and for
the
> >> aided eye?
Comparing the unaided eye to the aided eye can easily be invalidated as you
are comparing apples and oranges :o) Your self-referential model failed at
first attempt !!
Why not compare a 1x7 telescope and an 7x7 telescope, since the only
variable remaining will be the magnification. For that matter, you can use
any telescope, as long as you vary magnification (and keep in mind that some
eyepieces may be better than others). The test would be most decisive on
"pinpoint" sources at the edge of detectability, but since the eye has an
about 50-fold decrease in resolution as you go from bright objects to
extremely dim objects, the requirement for a pinpoint changes as well.
>
> > That suggest a non-linear fit !!
>
> The issue isn't whether the response of the eye is non-linear, but
> rather whether the magnification made a difference in the detectability.
Do the test!
>
> > I have tried to do this, have you ?
>
> I have tried to see objects near the threshold of detectability for
> telescopes of given apertures.
But have you tried various magnifications ?
>
> >>> Pluto is fex simple in my telescope (12") at around 260x on a dark
> >>> night, but impossible at 78x (perhaps not impossible, but I have not
> >>> succeded yet)...
>
> >> Fex?
>
> > For example
>
> You act as if that is common knowledge. I've never seen it used before.
Sorry if it wasn't...
>
> >> A 12-inch telescope is not a 3.7-inch telescope. I expect Pluto to be
> >> visible through a 12-inch.
>
> > Do you expect to see it at 78x ?
>
> I expect aperture to be more important than magnification.
But do you expect it to be visible at 78x ? I originally did, but I have not
succeded - and the eyepiece used to give 78x (Pentax 40mm) has fewer lenses
and higher transmission than the eyepiece used to give 260x (Nagler 12mm,
when Pluto is simple on a good night)
>
> > Even soo, I have spotted it in my 6" once (on a very good night)
>
> A 6-inch telescope is not a 3.7-inch telescope.
...but it is less than what is commonly said to be required to detect Pluto.
Perhpas if you also factor in seeing, transparency, and exceptional eye's,
that a 3.7" is possible. I donät say this is the case, only that your
statement that it isn't leaves a lot do be desired...
And on a perfect night, with a perfect eye, it may possible - and with a
higher probability if you use a small exit-pupil (high magnification) than
otherwise.
>
> > - I know I spotted it, because the 6":er (MK67) was piggybacked on the
> > 12":er (LX200) making one heck-of-a impressive double-barrel shotgun !!
>
> How does that prove that you saw it through the 6-inch? The imagination
> can take over, especially in this situation, given that you knew what to
> expect from the view through the 12-inch.
>
> > I did this expecting not to see Pluto,
>
> But you knew where to expect it. So one brief spot could be
misinterpreted
> as Pluto becoming visible during a moment of really good seeing, when it
> could just be some physical effect unrelated to any photon stimulus.
Again, your assumptions misleads you.
>
> > but it turned out that I could easily make it
> > out when using averted vision along a few stars of similar brightness.
>
> Having had the larger telescope to show you what to expect. Not a very
> good test. Get someone to point the 6-inch telescope at several points
> in the sky without your knowledge of the contents of the fields. Sketch
> what you see. Then compare with reality. That would be a much better
> test of the true limiting magnitude.
>
> > A 90/10 detection with the 6":er if you want to know how certain I am,
> > and clear a confirmation using the 12":er.
>
> My own tests had a built-in means of confirmation. If what I saw was
> real, then I should have been able to center the object in the aperture
> of a single aperture photometer and measure the brightness. The
> published results show just how faint it was possible to work (and there
> was plenty of magnification).
Did you try changing the magnification ?
>
> > Now, my eye's are perhaps not the most sensitive ones,
>
> That the sensitivity of eyes varies from person to person is well known.
>
> > it is difficult for me to say anything about somebody elses detection
> > in a 3.7":er,
>
> Did you notice that I didn't say anything about whether that person's
> detection was real or not? I simply noted that such a detection implies
> that that person's naked eye should be able to see magnitude 8. That's
> when the suggestion was made that such a conclusion doesn't necessarily
> follow due to the alleged magnification effect.
The magnification effect is there, whether you like it or not. The issue is
in reality what causes this...
To screen out all the other factors involved here, the result can only
become a statistical evaluation. If you require absolute proof, then it will
not be possible.
One possible explanation (partial as it may be) is that a smaller exit-pupil
will work better together with the eye, and improve detectability. Another
one is that the eye does not respond linearily to photons, meaning that 40
photons in one second does not necessaily detect twice as well as 20 photons
a second. Given the amount of processing done by the eye and by the brain,
and the complex behaviour of rods and cones, I would find this implausable
at all. Yet the eye is automatically assumed to behave nice and linearily !!
By assuming that the eye behaves linearily, a "detection-test" can and
probably will be interpreted incorrectly.
>
> > perhaps it is possible.
>
> I'd like to see the test performed.
Me too - but in the meantime, all that can be said is that detection is not
magnification (exit-pupil) independant as usually claimed...
>
> > At least my experience tells me that many things usually
> > considered impossible turns out to be possible when done correctly.
>
> My experience tells me that something thought to be possible wasn't
> really possible when a scientific study is done correctly. Do at
> least a single-blind test sometime.
Once upon a time, the bumblebee was prooven not to be able to fly under the
assumption that the wings where rigid. Since the bumblebee does fly, we must
assume that the model was incorrect, and as it turns out the problem was
exactly that. The bumblebee does not have rigid wings, and when a correct
model was used for it's wings, the problem was resolved.
>
> > Detection of Pluto with a 6":er is also considered impossible when using
> > a most models...
>
> Considered impossible by whom?
Apply m0 + 5*log(D / d) on a night whith a confirmed mag 6.5 transparency
and a 7mm pupil, and you should not be able to detect Pluto with a 6":er.
Period !
Since I reject the use of that formula unless m0 is made up as a function of
magnification (exit-pupil), I consider detection with a 6":er very much
possible...
Clear Skies,
Magnus
>
Magnus Nyborg
"Chosp" <ch...@home.com> wrote in message
news:awxP6.30038$vf6.3101451@news1.rdc1.sdca.home.com...
>
> "The Small Kahuna" <per...@company.com> wrote in message
> news:3B0DA38B...@company.com...
>
> > In addition it has an albedo function as well and so will reflect
> > sunlight. After all, it *has* to, unless it is a black hole. However,
> > since it is also stated that it is approximately 9 times further than
> > Pluto right now, it will be 81 times dimmer. (1/9^2) Because the
> > reflected light is so much dimmer, we will also ignore it too.
In fact, with Planet-X 9 times further than Pluto, then planet-X would be
about 9^4 = 6561 times dimmer than Pluto, if it were the same size and
albedo as Pluto. Since it is claimed tom be about 4 times the size of Earth,
this would increase it to be about 20 times larger than pluto, or 400 times
brighter. Left is the albedo, which if we assume as low as 0.02 (a fraction
of 10 to Pluto, about the lovest ever seen), this leaves us:
400 / 6561 / 10 ~= 1/160, or 5.5 magnitudes dimmer than Pluto.
Given this, Planet-X should be around magnitude 19.5-20.0 or probably a lot
brighter...like mag 17-17.5...
But of course, this is only reality-checked calculations - why should that
have any significance on a figment of somebodys imagination :o)
Clear Skies,
Magnus
tho...@antispam.ham
> In fact, with Planet-X 9 times further than Pluto, then planet-X would be
> about 9^4 = 6561 times dimmer than Pluto, if it were the same size and
> albedo as Pluto.
Incorrect; recall that Nancy claimed that the object doesn't reflect any
light, therefore the fourth power isn't the correct power to use. Given
that it is allegedly visible solely by emitted light, then inverse square
is the correct power law to use.
tho...@antispam.ham
> [...]
Any particular reason for your snippage?
>>> Stars are for all practical purposes pinpoints up to magnification of
>>> about 150x in a 12" at my location on most nights.
>> What are "practical purposes" in the context of this discussion?
> When observing visually, for "practical reasons" means that you cannot
> distinguish between a true pinpoint, and a star.
What is a "true pinpoint" in this context?
> [...]
Any particular reason for your snippage?
>>> Does the camcorder have auto-dark set for the background ?
>> No.
>>> Don't compare a camcorder with an eye, there is no comparison.
>> In the case of magnification enhancing detectability, one can make a
>> comparison, and in this case, the camcorder performed in a way that
>> you've been claiming for the eye.
Note: no response.
>>> They don't work the same !
>> Irrelevant, given that I didn't say they do.
> Irrelevant since I claim they don't !
But I described a case where the camcorder did have a fainter threshold
after applying magnification.
> [...]
Any particular reason for your snippage?
>>> Siliness! If the model is incorrect, it does not matter if you think it
>>> is selfreferential ! Being selfreferential is not a guarantee for
>>> correctness...
>> It is a guarantee for circular reasoning in this case.
> ....and if your reasoning is wrong, you will never escape the loop !!
The key word here is "if".
> [...]
Any particular reason for your snippage?
>>> Mainly since the smaller exit-pupil of the eyepiece reduces the
>>> aberrations induced by the eye's single (chromatic and spherical
>>> aberration) lens.
>>> A F/2 eye _must_ be much worse than an F/10 eye (not knowing the real
>>> parameters here). The brain processes much of the chromatic and possibly
>>> spherical aberrations out.
>> And how does the convergence of the light cone affect transmission?
> It doesn't, it creates a better focussed image, with a higher "Strehl" which
> results in a brighter image!
How does it change the Strehl???
> Since this is basic optical theory, I have to assume that you don't really
> know aboput these things!
I just concluded the same thing about you. There is a BIG difference
between magnification and focus. It's easy to increase magnification,
but how will that necessarily change the Strehl?
>>>>> 2. The eye is not a linear device, and a larger magnification will
>>>>> some times (many times) improve the contrast against the background. A
>>>>> linear device can not do this.
>>>> For objects that are truly point sources. But see above.
>>> Not only for objects that are pinpoints, the effect is often referred to
>>> while locating dim fuzzies...
>> How does magnification improve contrast on "dim fuzzies"?
> It shouldn't, according to the linear model, but it does, as real
> observations show!
Perhaps you'd like to present some of those "real observations"?
> [...]
Any particular reason for your snippage?
>>> Yes, a real test takes a lot of preparations - would you like to carry
>>> them out.
>> Sure, I'd be happy to. Would you like to fund them?
> So, whe have a stalemate here - you refusing to learn,
Where have I allegedly refused to learn anything?
> and me unable to provide the funds!
Too bad. I'm certainly not going to buy an airline ticket to fly to
Knisely's place. And the experiment could be open ended, with claim
after claim that the conditions weren't good enough that night to
reach the previously attained limit. Or he could simply claim that
he's older now and his eyes aren't as good; we can't reverse the
clock.
>>> If you don't, stop hiding behind a blanket of selfricheousness...
>> I'm not hiding at all; I'm discussing the issue right here, out in the
>> open. Furthermore, you're erroneously presupposing the existence of
>> some "blanket of selfricheousness".
> Citing a well known poster in this group "Dave Tholen is the junkyard
> dog of sci.astro"...
Who is this alleged "well known poster", and how does that justify your
claim of "selfricheousness"?
> It's not only me that believes this...
Who else? And you do realize that such reliance on invective doesn't
help your argument any, don't you? In fact, it weakens it, because
it's a well-known phenomenon that when some people start to realize
that they are losing an argument, they turn to insults in an attempt
to cut down the other person to at least the level at which they feel
they have been cut by having had bad arguments exposed.
>>> My observations are reported by others,
>> Which by definition makes them second hand.
> Correct! But does not make them untrue...
It provides the opportunity for misinterpretation. Ever play the game
called "Gossip" and compare the input with the output?
>>> and I am experienced enough to avoid fooling myself about detecting a
>>> star or something.
>> Doesn't that mean you're sure one way or the other?
> Given the statistical probability, you cannot be sure.
In other words, you wish to argue that you're not sure you saw the
words of my reply on your computer screen?
> Heard about sigma-2, sigma-3, sigma-5 etc ??
Absolutely; I've computed such numbers many times.
>>> If I have a 50/50 detection, I say soo...
>> Which means you're not sure, which means you might be fooling yourself.
> Which means that I if 1000 observers have a 50/50 detection, they
> practically confirm eachothers observation.
1000 out of how many? If it's 1000 out of 1000, then it wasn't a 50/50
detection, by definition.
> Heard about statistical probability ??
Absolutely; I compute such numbers rather often.
>>>>> Not having a scientificly explained model for the eye, this can not be
>>>>> proven with mathematics, but clearly the eye can be proven to _not_ be
>>>>> linear using a very simple test.
>>>> That the eye is not a linear device is not the issue.
>>> Ooh, but it is -
>> On the contrary, the issue is detectability as a function of
>> magnification.
> ....which if true requires that the eye does not behave in a simplified
> linear model.
Irrelevant, given that the nonlinearity of the eye isn't the issue
here.
> What part do you have problem understanding ?
You're erroneously presupposing that I don't understand some part of
the problem.
>>> you not understanding that it is,
>> Balderdash; you can't pontificate about my alleged misunderstanding and
>> use that to justify a change in the issue.
> Perhaps it is time for you to ponder what "improved detection as a function
> of magnification" actually implies.
Perhaps it is time for you to ponder that the nonlinear response of the
eye is not a sufficient argument to guarantee that the eye will see
fainter with magnification.
>>> does not change the fact
>>> ! The eye being an non-linear device is what causes many of the observed
>>> situations...
>> The eye being non-linear is why the magnitude system is logarithmic.
>> That doesn't prove that magnification enchances detectability.
> The non-linearity we are talking about is whether detection is governed by
> m0 + 5*log(D/d) or not.
And your explanation isn't sufficient. Simply claiming non-linearity
won't guarantee that the eye will see fainter with magnification.
> Using a linear model of the eye (as a functiona of magnification)
> requires that m0 is held constant as magnification changes.
That is also not a sufficient argument.
> Now, do you believe that m0 is constant over a range of magnifications ?
What I believe is irrelevant. The claim has been made that the number is
not constant over a range of magnifications, and I've solicited an
explanation for the phenomenon. I'm still waiting for one.
>>> A linear device would follow the formula m0 + 5*log( D / d) slavishly,
>>> regardless of magnification.
>> A non-linear device could also follow some formula slavishly, regardless
>> of magnification.
> It could...
Which means your argument is not sufficient.
>>> The reported behaviour is _not_ following the formula,
>> *Your* reported behavior does not follow the formula.
> More people than me have this reported...
While others have not.
> Yes, my report is also that the formula is not correct!
I'm well aware of what your report is.
>>> many contradictions reported,
>> No sufficient explanation provided.
> The linear model has been rejected by observations,
Your observations, not mine.
> although the observations have not been carried out in a scientific
> manner. This cast's doubt on the current interpretation, if not more...
>
> Plausable explanations have been provided,
Simply stating that the eye's response is non-linear isn't sufficient.
I could state that my shirt is red, and not only is it plausible, it's
a fact at the moment. It's also quite irrelevant. That the eye's
response is non-linear is also a fact, but you haven't demonstrated
any relevance for that fact.
> although I realise that you have not understood them.
An incorrect realization on your part.
>>> QED: The linear formula is not correct!
>> That doesn't logically follow. It has happened on many occasions that
>> someone can get the right answer for the wrong reasons. You've personally
>> observed a phenomenon; just because you've been able to come up with only
>> one explanation for that phenomenon does not guarantee that your
>> explanation is the correct one. See below for some other options.
> I have only rejected the common explanation!
Only the contrary, you have rejected all but the "magnification"
explanation.
>>> The behaviour is more that of an initially increasing m0 (from perhaps
>>> 6.5 to maybe 8.0) as magnification becomes larger and closes in on around
>>> 1mm exit-pupil.
>> What is special about 1 mm? Why not 0.5 mm? 0.1 mm?
> Nothing special at all about 1mm, but it looks like the change comes to a
> halt around 1mm...
Then there is something special about it. Can you explain it?
> from observations it also seems that it may decrease with
> even smaller exit-pupils, which would not be surprising.
Can you explain that?
>>> [Disclaimer: Even if the behaviour of the eye is not linear, it can be
>>> made up of linear devices]
>> Also irrelevant to the issue of magnification enhancing detectability.
> Perhaps, and perhaps not! Given that I have not come up with the correct
> explanation, only rejected the current explanation as insufficient, it is
> impossible to really say...
Only the contrary, you have rejected all but the "magnification"
explanation.
>>>>> Detection of faint objects can easily be shown to be improved when
>>>>> using higher magnificatiosn.
>>>> Which is a restatement of the original claim for which I'm requesting
>>>> an explanation.
>>> The evidence is only indicative, I have checked myself and talked to a
>>> few people, that's all.
>> I have my own experience as well.
>>> I know of no thourough study of this phenomenon,
>> Yet you seem to be convinced of the One True explanation, namely
>> magnification.
> ....since magnification changes many of the parameters of visual observation
> (which by the way the unaided eye cannot) I would think that this should not
> come as a surprise to you.
Actually, there are some changes that can be made. Perhaps you've heard
of the claim that the naked eye can see stars in the daytime by looking
through a long tube (with no optics) or from the bottom of a deep well?
>>> but many have reported what appears as confirmation.
>> If one person can imagine seeing something below what is normally
>> considered the threshold of detectability, then it is reasonable to
>> assume that others could also imagine seeing something below what is
>> normally considered the threshold of detectability. This discussion
>> isn't too different from the ones involving speaker wire, for example.
>> Can you hear a difference? Perhaps you've read about double-blind
>> testing? Has it been done in this case?
Note: no response.
>>> Sorry, I am only one guy, as representative as I hope I am.
>> And it's entirely possible for one guy to honestly claim that they saw
>> Pluto through a 3.7-inch telescope without having actually seen it,
>> given that the imagination can take over when working near thresholds,
>> especially when they know something is supposed to be there.
Note: no response.
>>> My claims are that:
>>> 1. The eye is not linear
>> Irrelevant, given that I never said it isn't.
> Relevant, since you claim that all reported phenomenon that does not follow
> the linear formula is figments of imagination
Where did I allegedly make that claim? I'm putting you on the spot right
here and now. That I made such a claim is a figment of YOUR imagination,
which I find rather ironic.
Once again, I should reproduce exactly what I have written:
DT] I've consistently avoided making any claims about what is and what is
DT] not humanly possible, because I know that not all eyes are alike.
DT] However, the greater the departure from the norm, the lesser the
DT] probability. Perhaps you've heard the phrase that extraordinary
DT] claims require extraordinary proof.
> - I claim that the linear model is incorrect...
I'm well aware of your claim. What I'm after is an explanation.
>>> 2. That m0 (in the formule m0 + 5*log(D / d) is dependant of
>>> magnification (which is the same as saying that the eye is not linear)
>> On the contrary, those are substantially different claims. A detector
>> can have non-linear response and still be independent of some effect.
> Incorrect, a linear model of the eye, _results_ in the formula above...
On the contrary, the non-linear response of the eye is why there is a
log in that formula in the first place!
>>> and increases a little when going from a 7mm exit-pupil to a 1mm pupil.
>> Can you explain that?
> I have been doing that for some time now!
On the contrary, you've merely repeated the claim. You've not offered
an explanation for why the eye is supposedly able to see fainter with
the aid of magnification.
> Why the eye behaves like this is up for interpretation,
The "why" is exactly what I've been asking for, and yet you just finished
telling me that you've been providing the explanation for some time now.
> but that it does behave like this seems both plausable and at least to
> some extent confirmed by severl/many observers around the globe.
And not confirmed by others.
>>> More factors than this have to be considered, like seeing, transparenty,
>>> lightpollution etc,
>> Not when the claim in question is restricted to magnification.
> First take into account the effects above,
Which ones, specifically?
> then add the effect of magnification.
Which does what?
> Transparency can of course not be neglected if you are going
> to try detection of Pluto in a 3.7":er, or 6":er for that matter...
Nor can altitude. You do realize that the eye works more poorly as
the amount of oxygen is reduced? The sky doesn't look quite as
fantastic from the summit of Mauna Kea as it does from the top of
Saddle Road.
>>> but what remains is a clear indication that m0 is
>>> magnification-dependant.
>> How can you be sure? To change magnification, you presumably changed the
>> eyepiece. Maybe the shorter focal length eyepiece had fewer optical
>> elements and transmitted more light. Maybe it had better antirelection
>> coatings. Maybe it had a better design to correct for various kinds of
>> aberrations. Yet for some reason, you're convinced that none of those
>> are factors, and that it MUST be magnification.
> You are assuming that I don't know what I am doing :o)
Balderdash; I've made no assumption here. I've simply stated some
potential factors that have not been addressed.
> Since you obviously don't understand what I am talking about, and don't
> intend to do, I can do nothing more...
That's classic pontification. Another sign of a weak argument.
>>> Perhaps if you looked through your own scope and tested detecting dim
>>> objects that you would become convinced that at least the linear model
>>> for the eye is not complete.
>> I have, and I do not have any evidence to support the conclusion that
>> magnification enhances detectability. I have not discussed any linear
>> model for the eye. The eye, like the ear, is known to not be a linear
>> detector. That's why stars visible to the naked eye range in brightness
>> by about a factor of 100 (excluding the Sun) but were assigned magnitudes
>> that range (historically) from about 1st to 6th magnitude.
> A veeeery simple question - have you tried limit-detections of objects using
> different magnifications ? If not, come back when you have !!
I'm back; it wasn't necessary to leave.
>>>>> Just try to located an object close to the limits of
>>>>> the telescope using
>>>>> 1. 5 exit-pupil, and...
>>>>> 2. 1 mm exit-pupil
>>>>>
>>>>> ....and compare the results.
>>>> How about comparing the limiting magnitude for the naked eye and for
>>>> the aided eye?
> Comparing the unaided eye to the aided eye can easily be invalidated as you
> are comparing apples and oranges :o) Your self-referential model failed at
> first attempt !!
I see that you removed two levels of indentation. Another sign of a
failing argument.
> Why not compare a 1x7 telescope and an 7x7 telescope, since the only
> variable remaining will be the magnification.
How can you say that?
> For that matter, you can use any telescope, as long as you vary
> magnification (and keep in mind that some eyepieces may be better
> than others).
Tell me, did you bother to read what I wrote?
DT] How can you be sure? To change magnification, you presumably changed the
DT] eyepiece. Maybe the shorter focal length eyepiece had fewer optical
DT] elements and transmitted more light. Maybe it had better antirelection
DT] coatings. Maybe it had a better design to correct for various kinds of
DT] aberrations.
> The test would be most decisive on
> "pinpoint" sources at the edge of detectability, but since the eye has an
> about 50-fold decrease in resolution as you go from bright objects to
> extremely dim objects, the requirement for a pinpoint changes as well.
Can you explain that?
>>> That suggest a non-linear fit !!
>> The issue isn't whether the response of the eye is non-linear, but
>> rather whether the magnification made a difference in the detectability.
> Do the test!
What makes you think I haven't?
>>> I have tried to do this, have you ?
>> I have tried to see objects near the threshold of detectability for
>> telescopes of given apertures.
> But have you tried various magnifications ?
Of course.
>>>>> Pluto is fex simple in my telescope (12") at around 260x on a dark
>>>>> night, but impossible at 78x (perhaps not impossible, but I have not
>>>>> succeded yet)...
>>>> Fex?
>>> For example
>> You act as if that is common knowledge. I've never seen it used before.
> Sorry if it wasn't...
>>>> A 12-inch telescope is not a 3.7-inch telescope. I expect Pluto to be
>>>> visible through a 12-inch.
>>> Do you expect to see it at 78x ?
>> I expect aperture to be more important than magnification.
> But do you expect it to be visible at 78x ?
I expect aperture to be more important than magnification.
Or let me see if you can understand my response by replacing your
question with the following:
"Do you expect to see it wearing a red shirt?"
> I originally did, but I have not succeded - and the eyepiece used to give
> 78x (Pentax 40mm) has fewer lenses and higher transmission than the
> eyepiece used to give 260x (Nagler 12mm, when Pluto is simple on a good
> night)
Higher transmission at what wavelengths? And what about aberrations?
>>> Even soo, I have spotted it in my 6" once (on a very good night)
>> A 6-inch telescope is not a 3.7-inch telescope.
> ....but it is less than what is commonly said to be required to detect
> Pluto.
What is commonly said to be required?
> Perhpas if you also factor in seeing, transparency, and exceptional eye's,
> that a 3.7" is possible.
And when do you start to question the veracity of a claim? Suppose
somebody comes along and claims to have seen Pluto through a 3.5-inch?
And then next year another person claims 3.2-inch? And the year after
that another claims 2.7-inch? When when you start to wonder?
> I donät say this is the case, only that your
> statement that it isn't leaves a lot do be desired...
I haven't said it isn't possible:
DT] I've consistently avoided making any claims about what is and what is
DT] not humanly possible, because I know that not all eyes are alike.
DT] However, the greater the departure from the norm, the lesser the
DT] probability. Perhaps you've heard the phrase that extraordinary
DT] claims require extraordinary proof.
> And on a perfect night, with a perfect eye, it may possible - and with a
> higher probability if you use a small exit-pupil (high magnification) than
> otherwise.
Is it possible through a 3.5-inch under such conditions? A 3.2-inch?
A 2.7-inch?
>>> - I know I spotted it, because the 6":er (MK67) was piggybacked on the
>>> 12":er (LX200) making one heck-of-a impressive double-barrel shotgun !!
>> How does that prove that you saw it through the 6-inch? The imagination
>> can take over, especially in this situation, given that you knew what to
>> expect from the view through the 12-inch.
Note: no response.
>>> I did this expecting not to see Pluto,
>> But you knew where to expect it. So one brief spot could be
>> misinterpreted as Pluto becoming visible during a moment of really
>> good seeing, when it could just be some physical effect unrelated
>> to any photon stimulus.
> Again, your assumptions misleads you.
Where have I allegedly been misled?
>>> but it turned out that I could easily make it
>>> out when using averted vision along a few stars of similar brightness.
>> Having had the larger telescope to show you what to expect. Not a very
>> good test. Get someone to point the 6-inch telescope at several points
>> in the sky without your knowledge of the contents of the fields. Sketch
>> what you see. Then compare with reality. That would be a much better
>> test of the true limiting magnitude.
Note: no response.
>>> A 90/10 detection with the 6":er if you want to know how certain I am,
>>> and clear a confirmation using the 12":er.
>> My own tests had a built-in means of confirmation. If what I saw was
>> real, then I should have been able to center the object in the aperture
>> of a single aperture photometer and measure the brightness. The
>> published results show just how faint it was possible to work (and there
>> was plenty of magnification).
> Did you try changing the magnification ?
Absolutely.
>>> Now, my eye's are perhaps not the most sensitive ones,
>> That the sensitivity of eyes varies from person to person is well known.
>>> it is difficult for me to say anything about somebody elses detection
>>> in a 3.7":er,
>> Did you notice that I didn't say anything about whether that person's
>> detection was real or not? I simply noted that such a detection implies
>> that that person's naked eye should be able to see magnitude 8. That's
>> when the suggestion was made that such a conclusion doesn't necessarily
>> follow due to the alleged magnification effect.
> The magnification effect is there, whether you like it or not.
Evidence, please.
> The issue is in reality what causes this...
Perhaps the cause is unrelated to magnification.
> To screen out all the other factors involved here, the result can only
> become a statistical evaluation.
Why do you say that?
> If you require absolute proof, then it will not be possible.
Why do you say that?
> One possible explanation (partial as it may be) is that a smaller exit-pupil
> will work better together with the eye, and improve detectability.
What makes it better?
> Another
> one is that the eye does not respond linearily to photons, meaning that 40
> photons in one second does not necessaily detect twice as well as 20 photons
> a second.
We already know that the eye does not response linearly. We also already
know that my shirt is currently red. How are those facts relevant?
> Given the amount of processing done by the eye and by the brain,
> and the complex behaviour of rods and cones, I would find this implausable
> at all.
Why do you suddenly find it implausable [sic]?
> Yet the eye is automatically assumed to behave nice and linearily !!
By whom?
> By assuming that the eye behaves linearily, a "detection-test" can and
> probably will be interpreted incorrectly.
Who is allegedly making such an assumption?
>>> perhaps it is possible.
>> I'd like to see the test performed.
> Me too - but in the meantime, all that can be said is that detection is not
> magnification (exit-pupil) independant as usually claimed...
How can you even say that?
>>> At least my experience tells me that many things usually
>>> considered impossible turns out to be possible when done correctly.
>> My experience tells me that something thought to be possible wasn't
>> really possible when a scientific study is done correctly. Do at
>> least a single-blind test sometime.
> Once upon a time, the bumblebee was prooven not to be able to fly under the
> assumption that the wings where rigid. Since the bumblebee does fly, we must
> assume that the model was incorrect, and as it turns out the problem was
> exactly that. The bumblebee does not have rigid wings, and when a correct
> model was used for it's wings, the problem was resolved.
Suppose the claim was that the bumblebee could fly because of its color?
Right answer; wrong explanation.
>>> Detection of Pluto with a 6":er is also considered impossible when using
>>> a most models...
>> Considered impossible by whom?
> Apply m0 + 5*log(D / d) on a night whith a confirmed mag 6.5 transparency
> and a 7mm pupil, and you should not be able to detect Pluto with a 6":er.
> Period !
According to whom?
> Since I reject the use of that formula unless m0 is made up as a function of
> magnification (exit-pupil), I consider detection with a 6":er very much
> possible...
How about a 5-inch? Or a 4-inch? 3-inch? 2-inch? Where do you cross
the line of credibility?
Magnus Nyborg
<tho...@AntiSpam.ham> wrote in message
news:01hQ6.7454$WI.21...@typhoon.hawaii.rr.com...
Actually, this is a correct description of a real situation, since as you
yourself states "Nancy does not now what she is talking about"...
But then again, you dont seem to know what you are talking about either !
Clear Skies,
Magnus
>
Magnus Nyborg
<tho...@AntiSpam.ham> wrote in message
news:fshQ6.7455$WI.21...@typhoon.hawaii.rr.com...
[...] Snipped for brewity, and there was a lot to snip...
Two simple questions - do you think that the fully dilated eye is
diffraction-limited, and can you accept that as the pupil decreases, the
diffraction-performance (Strehl) increases?
Clear Skies,
Magnus
Bill Nelson
:> Why do you not include the fact that she said it was visible
:> as a 2nd magnitude object which changed to 11th magnitude
:> as it came closer?
: Why is it you fail to register the difference between ABSOLUTE and
: APPARENT magnitude?
Shame, shame, Nancy. It has been obviously clear that you have never
had the slightest idea about various methods of stating visual magnitude.
If you do now, it is because you have been doing some reading. If you
have, keep it up. There may be some small amount of hope for you.
--
Bill Nelson (bi...@peak.org)
tho...@antispam.ham
>>> In fact, with Planet-X 9 times further than Pluto, then planet-X would
>>> be about 9^4 = 6561 times dimmer than Pluto, if it were the same size
>>> and albedo as Pluto.
>> Incorrect; recall that Nancy claimed that the object doesn't reflect any
>> light, therefore the fourth power isn't the correct power to use. Given
>> that it is allegedly visible solely by emitted light, then inverse square
>> is the correct power law to use.
> Actually, this is a correct description of a real situation, since as you
> yourself states "Nancy does not now what she is talking about"...
>
> But then again, you dont seem to know what you are talking about either !
On what basis do you make that ridiculous claim?
josX
1. It didn't chance as it came closer, both statements were in the *same*
piece of zetatalk.com text. I quoted that already so here is the URL:
http://www.zetatalk.com/poleshft/p29.txt.
2. An Solar-system object's absolute Magnitude is the aparent magnitude
were you no 1AU. So since the P-X is at 9 PLuto-Sun distances, that
absolute magnitude number will be MUCH brighter than it's *aparent*
magnitude.
In other words: Nancy was EXACTLY right, as in /spot on/, even though she
has no astronomy knowledge, which would seem to indicate her source does
have this knowledge. Yeah: let the emotions take over now... hehehe, sorry
guys, but that is what logic says, deal with it.
This Magnitude 2.0 or 11 is also non issue, and a time-waster btw too! :((.
regards,
Jos
(ps, can't find the size of the dust-cloud right now...)
--
tho...@antispam.ham
> In other words: Nancy was EXACTLY right, as in /spot on/,
About what, allegedly?
> even though she has no astronomy knowledge,
Other than what she's picked up from those of us countering her
false statements.
> which would seem to indicate her source does have this knowledge.
Like those of us countering her false statements.
> This Magnitude 2.0 or 11 is also non issue,
On what basis do you make that claim? You like to ignore
inconsistencies?
tho...@antispam.ham
> [...] Snipped for brewity, and there was a lot to snip...
Much of it yours, but I'm disappointed that you chose not to
address the matters I raised.
> Two simple questions - do you think that the fully dilated eye is
> diffraction-limited, and can you accept that as the pupil decreases, the
> diffraction-performance (Strehl) increases?
Of what relevance are those questions to the issue of telescopic
magnification affecting the threshold of detection.
Magnus Nyborg
<tho...@AntiSpam.ham> wrote in message
news:VFoQ6.7489$WI.21...@typhoon.hawaii.rr.com...
> Magnus Nyborg writes:
>
> > [...] Snipped for brewity, and there was a lot to snip...
>
> Much of it yours, but I'm disappointed that you chose not to
> address the matters I raised.
Tholen, come on - you don't raise matters, you object. This is all that you
do...at least admit to that! There is not _one_ single response from you in
this newsgroup that does anything but that. I used to do like that when I
was 5 years old...time to grow up!!
And besides, I had to go to work! A cup of coffe, a little juice, a sandwich
and a quick look at what news you could possibly bring this wonderfull
morning - none, as I expected! And certainly none that deserves a response!!
>
> > Two simple questions - do you think that the fully dilated eye is
> > diffraction-limited, and can you accept that as the pupil decreases, the
> > diffraction-performance (Strehl) increases?
>
> Of what relevance are those questions to the issue of telescopic
> magnification affecting the threshold of detection.
You are only dodging the question. It is a simple one, taking only a simple
answer, but then you don't explain or answer, you only object (and badly at
that)
The correct answer is that with a smaller exit-pupil from the teleskope, the
detection in the eye will become easier as the diffractionimage becomes
better making the contrast higher. This applies trivially until the
pointsource on the retina is no longer a pointsource. But as we experienced
observers soon realise, it actually applies for even higher magnification
(smaller exit-pupils), and this actually extends even to "dim fuzzies" that
take up a considerable angle at high magnifications.
Let's cut to the chase - the model you are desperately defending is the
following...
1. The naked eye can on an good night detect mag 6.0 (this is the definition
used to define the magnitude scale). The magnitude-scale is logaritmical
such that 100x brighter represents exactly -5 magnitudes.
2. The naked eye can dialate up to about 8mm on young people, and perhaps
5mm on old people - I will use d=7mm here since I still consider myself
young...
3. A telescope gathers more light according to (D/d)^2, but it also
introduces some losses. For a SCT the accumulated losses using a diagonal
and an high-transmission eyepiece are very close to 30%. This number can
even be larger.
m_l = 6.0 + 2.5*log( (D/d)^2 * 0.7) = 6.0 - 0.4 + 5*log(D/d) = 5.6 +
5*log(D/d)
My 12" would according to this formula be useful for detection down to m_l =
5.6 + 5*log(305/7) = 13.8, and Pluto would be extremely hard to detect on an
average night (actually impossible according to this formula right now). Yet
I find it very _easy_ to detect on an average night, and most of the time I
can see about 1 magnitude dimmer objects. On exceptional nights I can
probably see even more. And furthermore, I find it easier to detect as
magnification goes up (exit-pupil becomes smaller)
How do you explain that I and others easily detect Pluto with a 12":er (even
you expect it to be detected) and how do you explain people detecting it
with even smaller instruments ? You cannot claim that the average night is
better than mag 6.0, and you certainly cannot object to the model I used !
Why does using an eyepiece with less transmission and higher magnification
make it simpler to detect Pluto ? Why have I constantly failed at 78x but
find it simple at 260x and 520x (using a barlow = even more losses) ?
If you can answer these questions, we would all be _very_ thankful - please
dazzle us with your wisdom !! ;o)
My claim stands - m0 has an increasing slope depending on magnification
(exit-pupil), for me I would say m0 = 5.5 at e.p. = ~7.0 and about 7.5 for
e.p ~=1.0 (your mileage may vary). Other related factors cannot be ruled out
due to the small sample of data, but others report similar experiences
(well, not you of course, but you don't report anything so that does not
count in the first place)
Clear Skies,
Magnus