Today is the 400th Anniversary of Galileo Discovering Ganymede
giveitawhirl2008
he discoverd last Friday (400 years ago).
Let's go!
Steve Hayes
<giveitaw...@gmail.com> wrote:
>The other three Galilean moons of Jupiter - Io, Callisto and Europa -
>he discoverd last Friday (400 years ago).
>
>Let's go!
We can't.
--
Steve Hayes from Tshwane, South Africa
Web: http://hayesfam.bravehost.com/stevesig.htm
Blog: http://methodius.blogspot.com
E-mail - see web page, or parse: shayes at dunelm full stop org full stop uk
lorad
wrote:
The amazing thing is that he used a telescope that had less
magnification (20x) and smaller aperture than a cheap chinese $10 set
of chinese binoculars.
www.wwnorton.com/.../images/18thc/telescope.jp
No wonder he had red-rimmed eys:
http://en.wikipedia.org/wiki/File:Galileo.arp.300pix.jpg
Pat Flannery
> The amazing thing is that he used a telescope that had less
> magnification (20x) and smaller aperture than a cheap chinese $10 set
> of chinese binoculars.
Most binoculars have either 7X or 10X magnification; but the four moons
of Jupiter are visible through both magnifications.
Heck, I saw them once with my naked eye on a very clear, cold, and still
night by positioning myself so that Jupiter itself was occulted by a
thin twig on a tree around fifty feet from me.
All four have enough magnitude to be naked-eye visible, it's just that
the glare of Jupiter itself hides them from view.
My favorite was Galileo trying to figure out why Saturn looked so odd
through his telescope: http://galileo.rice.edu/sci/observations/saturn.html
Pat
Androcles
"Pat Flannery" <fla...@daktel.com> wrote in message
news:qq6dnWn8PM-qktPW...@posted.northdakotatelephone...
Now why would the name "Huygens" be in that URL?
http://galileo.rice.edu/images/things/hevelius_phases.gif
Now why would the name "Hevelius" be in that URL?
My favourite was Flannery trying to figure out why Galileo looked so
Huygens through his URL.
Greg D. Moore (Strider)
news:qq6dnWn8PM-qktPW...@posted.northdakotatelephone...
>> The amazing thing is that he used a telescope that had less
>> magnification (20x) and smaller aperture than a cheap chinese $10 set
>> of chinese binoculars.
>
> Most binoculars have either 7X or 10X magnification; but the four moons of
> Jupiter are visible through both magnifications.
I still recall the firs time I saw the moons of Jupiter. I used a pare of
binoculars.
VERY cool.
> Heck, I saw them once with my naked eye on a very clear, cold, and still
> night by positioning myself so that Jupiter itself was occulted by a thin
> twig on a tree around fifty feet from me.
> All four have enough magnitude to be naked-eye visible, it's just that the
> glare of Jupiter itself hides them from view.
> My favorite was Galileo trying to figure out why Saturn looked so odd
> through his telescope:
> http://galileo.rice.edu/sci/observations/saturn.html
>
>
>
> Pat
--
Greg Moore
Ask me about lily, an RPI based CMC.
Rich
> lorad wrote:
>> The amazing thing is that he used a telescope that had less
>> magnification (20x) and smaller aperture than a cheap chinese $10 set
>> of chinese binoculars.
>
> Most binoculars have either 7X or 10X magnification; but the four
> moons of Jupiter are visible through both magnifications.
> Heck, I saw them once with my naked eye on a very clear, cold, and
> still night by positioning myself so that Jupiter itself was occulted
> by a thin twig on a tree around fifty feet from me.
You need pretty acute vision to see it though.
Pat Flannery
>
> I still recall the firs time I saw the moons of Jupiter. I used a pare of
> binoculars.
>
> VERY cool.
Jupiter, the Moon, and Saturn are about the three most fun objects to
look at with a small telescope.
What amazed me was how fast the moons rotate around Jupiter, so that
their positions noticeably change in just a few hours.
At one time it was proposed that telescopic observations of them could
be used to determine a ship's longitude without carrying a chronometer
by carefully determining their positions relative to the planet and each
other and comparing that to drawings in a book that would show at what
exact time a certain alignment would occur.
Unfortunately, the pitching of the ship in the waves made the idea
impractical in a pre-gyro-stabilized era.
Pat
Androcles
Good grief! A remote clock that anyone can see from anywhere!
Doesn't that upset the "genius" Einstein's time dilation?
"If we assume that the result proved for a polygonal line is also valid for
a continuously curved line, we arrive at this result: If one of two
synchronous clocks at A is moved in a closed curve with constant velocity
until it returns to A, the journey lasting t seconds, then by the clock
which has remained at rest the travelled clock on its arrival at A will be
1/2 tv^2/c^2 second slow. Thence we conclude that a balance-clock at the
equator must go more slowly, by a very small amount, than a precisely
similar clock situated at one of the poles under otherwise identical
conditions." -- Albert Fuckwit Einstein.
Jonathan
"Greg D. Moore (Strider)" <mooregr_d...@greenms.com> wrote in message
news:48adncE8BdZ219PW...@earthlink.com...
> "Pat Flannery" <fla...@daktel.com> wrote in message
> news:qq6dnWn8PM-qktPW...@posted.northdakotatelephone...
>> lorad wrote:
>>> The amazing thing is that he used a telescope that had less
>>> magnification (20x) and smaller aperture than a cheap chinese $10 set
>>> of chinese binoculars.
>>
>> Most binoculars have either 7X or 10X magnification; but the four moons of
>> Jupiter are visible through both magnifications.
>
> I still recall the firs time I saw the moons of Jupiter. I used a pare of
> binoculars.
>
> VERY cool.
One of the best memories of my old Meade 10" scope was the first
time I saw IO emerge from behind Jupiter.
>
>> Heck, I saw them once with my naked eye on a very clear, cold, and still
>> night by positioning myself so that Jupiter itself was occulted by a thin
>> twig on a tree around fifty feet from me.
>> All four have enough magnitude to be naked-eye visible, it's just that the
>> glare of Jupiter itself hides them from view.
>> My favorite was Galileo trying to figure out why Saturn looked so odd through
>> his telescope:
A fuzzy image makes Saturn look like a planet with 'ears'.
giveitawhirl2008
Using the moons of Jupiter as a clock; now there's a cool idea!
http://www.amazon.com/Longitude-Genius-Greatest-Scientific-Problem/dp/0140258795
Androcles
"giveitawhirl2008" <giveitaw...@gmail.com> wrote in message
news:516f115f-0626-47a7...@m25g2000yqc.googlegroups.com...
============================================================
Not really. Ole Roemer used IO to measure the speed of light:
http://en.wikipedia.org/wiki/Ole_R%C3%B8mer
"When the angle is 180� the delay becomes 22 minutes, which may be
interpreted as the time necessary for the light to cross a distance equal to
the diameter of the Earth's orbit"
That's not much use to a navigator... Bristol is 10 minutes West of London,
he wouldn't know if he was in the North Sea or the Atlantic Ocean.
Using the GPS as a clock; now there's a red hot idea! And we do...
giveitawhirl2008
> On Tue, 12 Jan 2010 21:36:25 -0800 (PST), giveitawhirl2008
>
> >The other three Galilean moons of Jupiter - Io, Callisto and Europa -
> >he discoverd last Friday (400 years ago).
>
> >Let's go!
>
> We can't.
>
> --
> Steve Hayes from Tshwane, South Africa
> Web: http://hayesfam.bravehost.com/stevesig.htm
> Blog:http://methodius.blogspot.com
> E-mail - see web page, or parse: shayes at dunelm full stop org full stop uk
"We can't?"
Basically, i agree with you. Then again, within God's plan of history,
you never know what twists and turns human events (and natural ones)
might take.
Jesus said that He will return at an hour that "....you think not."
The ICR, http://www.icr.org/ , in a recent devotional, suggested that
He might return NOT when there is war and strife, but when things are
going "well." Maybe when man's systems - political, economic,
technological, etc. - seem finally to be "clicking" well, when there
is much peace and prosperity, etc., and man is thinking again he does
not need God...maybe THAT'S when Christ will return.
What more way to think we are self-reliant than, on top things on
Earth improvinig, we finally beginning to realize our dream of
expanding our civlization/commerce to the solar system, or even
beyond? Man really thought he was hot stuff by the time of the
nineteenth-turning-to-twentieth century. Darwinism telling us about
"the Ascent of Man," science and technology burgeoning; why, we could
even cross the Atlantic in four days with modern steam ships! They
even had an unsinkable ship which they referred to as "The ship God
Himself could not sink."
So, maybe God will choose to let us go on another several decades to a
century or more. By then, we might be establishing permanent outposts
on other worlds. If THAT doesn't make us feel like "Man is the measure
of all things".....!
Androcles
On Jan 13, 1:24 am, Steve Hayes <hayes...@telkomsa.net> wrote:
> On Tue, 12 Jan 2010 21:36:25 -0800 (PST), giveitawhirl2008
>
> <giveitawhril2...@gmail.com> wrote:
> >The other three Galilean moons of Jupiter - Io, Callisto and Europa -
> >he discoverd last Friday (400 years ago).
>
> >Let's go!
>
> We can't.
>
> --
> Steve Hayes from Tshwane, South Africa
> Web: http://hayesfam.bravehost.com/stevesig.htm
> Blog:http://methodius.blogspot.com
> E-mail - see web page, or parse: shayes at dunelm full stop org full stop
> uk
"We can't?"
Basically, i agree with you. Then again, within God's plan of history,
you never know what twists and turns human events (and natural ones)
might take.
Jesus said that He will return at an hour that "....you think not."
The ICR, http://www.icr.org/ , in a recent devotional, suggested that
He might return NOT when there is war and strife, but when things are
going "well." Maybe when man's systems - political, economic,
technological, etc. - seem finally to be "clicking" well, when there
is much peace and prosperity, etc., and man is thinking again he does
not need God...maybe THAT'S when Christ will return.
==============================================
He's have to be a dumb bastard to return after the last time
we kicked his arse out, and there are enough crosses and
churches in the shape of crosses to warn him to stay away,
numbskull.
I don't need your fuckin' gods, I'm not kissing any god's arse;
I'll die a man and go to oblivion and I'm not bothered about it
in the slightest. Now get the fuck out of sci newsgroups and
take your gods with you, you scared-to-die chickenshit wimp.
Pat Flannery
>> At one time it was proposed that telescopic observations of them could
>> be used to determine a ship's longitude without carrying a chronometer
>> by carefully determining their positions relative to the planet and each
>> other and comparing that to drawings in a book that would show at what
>> exact time a certain alignment would occur.
>> Unfortunately, the pitching of the ship in the waves made the idea
>> impractical in a pre-gyro-stabilized era.
>>
>> Pat
>
> Using the moons of Jupiter as a clock; now there's a cool idea!
> http://www.amazon.com/Longitude-Genius-Greatest-Scientific-Problem/dp/0140258795
The TV production of that book is really well done also:
http://www.amazon.com/Longitude-Jonathan-Coy/dp/B00004U2K1/ref=pd_sim_b_4
One non-starter idea for figuring out what time it is: two dogs from the
same litter of pups are raised together and treated with "The Oil Of
Sympathy"; one stays at the Royal Observatory at Greenwich, the other is
sent on a ship. When noon arrives, the dog at the observatory is
tortured a bit, and the one on the ship begins to howl...no matter where
in the world the ship is.
This is an early version of quantum entanglement, or as Einstein would
probably call it, "Snoopy action at a distance".
Pat
Pat Flannery
> So, maybe God will choose to let us go on another several decades to a
> century or more. By then, we might be establishing permanent outposts
> on other worlds. If THAT doesn't make us feel like "Man is the measure
> of all things".....!
Right now, my brother must be howling up in Grand Forks, as this is
certainly torture of some sort. ;-)
Pat
Eric Chomko
The most interesting use of the Jovian moons was Roemer trying to
guess the speed
of light. http://en.wikipedia.org/wiki/R%C3%B8mer%27s_determination_of_the_speed_of_light
Bill Owen
> The most interesting use of the Jovian moons was Roemer trying to
> guess the speed
> of light. http://en.wikipedia.org/wiki/R%C3%B8mer%27s_determination_of_the_speed_of_light
Or the timing of eclipses as a method of determining longitude. Jay
Lieske, before his retirement from JPL, found a veritable treasure trove
of 17th and 18th century eclipse observations, which helped constrain
the mean motion of the satellites before Galileo (the spacecraft) did it
far better.
http://adsabs.harvard.edu/abs/1986A%26A...154...61L
http://adsabs.harvard.edu/abs/1986A%26AS...63..143L
-- Bill Owen
giveitawhirl2008
> giveitawhirl2008 wrote:
> >> At one time it was proposed that telescopic observations of them could
> >> be used to determine a ship's longitude without carrying a chronometer
> >> by carefully determining their positions relative to the planet and each
> >> other and comparing that to drawings in a book that would show at what
> >> exact time a certain alignment would occur.
> >> Unfortunately, the pitching of the ship in the waves made the idea
> >> impractical in a pre-gyro-stabilized era.
>
> >> Pat
>
> >http://www.amazon.com/Longitude-Genius-Greatest-Scientific-Problem/dp...
>
> The TV production of that book is really well done also:http://www.amazon.com/Longitude-Jonathan-Coy/dp/B00004U2K1/ref=pd_sim...
> One non-starter idea for figuring out what time it is: two dogs from the
> same litter of pups are raised together and treated with "The Oil Of
> Sympathy"; one stays at the Royal Observatory at Greenwich, the other is
> sent on a ship. When noon arrives, the dog at the observatory is
> tortured a bit, and the one on the ship begins to howl...no matter where
> in the world the ship is.
> This is an early version of quantum entanglement, or as Einstein would
> probably call it, "Snoopy action at a distance".
>
> Pat
Quantum entanglement! That's what I was thinking as I read your
paragraph! :-)
I saw the show and it was quite interesting. I remember something
about torturing dogs in there. Yeah, the schemes just got crazier and
crazier. Obviously, what was really needed was what the guy came up
with: a clock that worked at sea. But as to unstable platforms for
astronomical observing: it almost seems to me that they should have
been able to come up with such a platform. If they had, they could
have even put a clock (of the regular kind for their day) on it, and/
or an astronomical observer. In fact, it seems to me that if no
mechanical system would have worked, they could have even had a team
of sailors - say half a dozen - whose job it was to keep such a
platform stable by hand, while the observer looked at the moons of
Jupiter, or whatever. But obviously, the mechanical clock that was
little effected by the ship's motion, is what was really needed. And
that's what the guy came up with.
Frank Robertson
> "giveitawhirl2008" <giveitawhril2...@gmail.com> wrote in message
>
> news:bb3faf13-f5d5-4c30...@e27g2000yqd.googlegroups.com...
> On Jan 13, 1:24 am, Steve Hayes <hayes...@telkomsa.net> wrote:
>
>
>
>
>
> > On Tue, 12 Jan 2010 21:36:25 -0800 (PST), giveitawhirl2008
>
> > <giveitawhril2...@gmail.com> wrote:
> > >he discoverd last Friday (400 years ago).
>
> > >Let's go!
>
> > We can't.
>
> > --
> > Steve Hayes from Tshwane, South Africa
> > Web:http://hayesfam.bravehost.com/stevesig.htm
> > Blog:http://methodius.blogspot.com
> > E-mail - see web page, or parse: shayes at dunelm full stop org full stop
> > uk
>
> "We can't?"
>
> Basically, i agree with you. Then again, within God's plan of history,
> you never know what twists and turns human events (and natural ones)
> might take.
>
> Jesus said that He will return at an hour that "....you think not."
> He might return NOT when there is war and strife, but when things are
> going "well." Maybe when man's systems - political, economic,
> technological, etc. - seem finally to be "clicking" well, when there
> is much peace and prosperity, etc., and man is thinking again he does
> not need God...maybe THAT'S when Christ will return.
> ==============================================
> He's have to be a dumb bastard to return after the last time
> we kicked his arse out, and there are enough crosses and
> churches in the shape of crosses to warn him to stay away,
> numbskull.
> I don't need your fuckin' gods, I'm not kissing any god's arse;
> I'll die a man and go to oblivion and I'm not bothered about it
> in the slightest. Now get the fuck out of sci newsgroups and
>
> - Show quoted text -
I don't think that kissing His arse would actually do you any good.
Just sounds like lip service, to me.
giveitawhirl2008
wrote:
>
> - Show quoted text -
Addendum: Oh...that platform may have been no good in storms! :-)
Androcles
"Frank Robertson" <laisre...@gmail.com> wrote in message
news:2f5bfcce-8034-4b0b...@b10g2000yqa.googlegroups.com...
I don't think
===============================================
Yes, I already gathered that, you've already made it rather obvious.
However, there is no requirement for you to flaunt your ignorant bigotry.
--Androcles
===============================================
Pat Flannery
> I saw the show and it was quite interesting. I remember something
> about torturing dogs in there. Yeah, the schemes just got crazier and
> crazier. Obviously, what was really needed was what the guy came up
> with: a clock that worked at sea. But as to unstable platforms for
> astronomical observing: it almost seems to me that they should have
> been able to come up with such a platform.
They show what they came up with in the miniseries; it's a weighted
chair and telescope suspended under a frame like a pendulum, but it
didn't stay stable enough to be of any use.
Then of course there would be cloudy nights to deal with.
> If they had, they could
> have even put a clock (of the regular kind for their day) on it, and/
> or an astronomical observer. In fact, it seems to me that if no
> mechanical system would have worked, they could have even had a team
> of sailors - say half a dozen - whose job it was to keep such a
> platform stable by hand, while the observer looked at the moons of
> Jupiter, or whatever. But obviously, the mechanical clock that was
> little effected by the ship's motion, is what was really needed. And
> that's what the guy came up with.
Another screwball plan was to build small artificial islands throughout
the oceans that would fire off large skyrockets on the hour that would
be observed by any ships in the vicinity.
Back to the dogs, it was apparently the Powder Of Sympathy, not a oil,
that was to be used; details here:
http://www.themodernword.com/eco/eco_longitude.html
The whole thing sounds like some early take on homeopathic medicine.
Pat
Eric Chomko
> Eric Chomko wrote:
> > The most interesting use of the Jovian moons was Roemer trying to
> > guess the speed
>
> Or the timing of eclipses as a method of determining longitude. Jay
> Lieske, before his retirement from JPL, found a veritable treasure trove
> of 17th and 18th century eclipse observations, which helped constrain
> the mean motion of the satellites before Galileo (the spacecraft) did it
> far better.
After the antenna glitch on Galileo it is encouraging to read about
something it did well.
>
> http://adsabs.harvard.edu/abs/1986A%26A...154...61Lhttp://adsabs.harvard.edu/abs/1986A%26AS...63..143L
>
> -- Bill Owen
Bill Owen
Thanks, Eric. The four Galileans are massive enough that their
gravitational signature showed up easily in the Doppler pretty much all
the time we were in orbit -- not just during flybys -- this meant that
the radio tracking data served so well to pin down Galileo's trajectory
that we could forgo optical navigation imaging after the first five or
six revolutions.
Galileo managed to get a lot done very well, despite the antenna glitch
and the resulting huge hit to the data volume. The satellite science
was just fine, the fields and particles stuff was OK -- the big loser
was atmospheric science, which was heavy on imaging. They got a lot of
that back during Cassini's flyby, and presumably even more from New
Horizons.
-- Bill
Pat Flannery
>
> Galileo managed to get a lot done very well, despite the antenna glitch
> and the resulting huge hit to the data volume. The satellite science
> was just fine, the fields and particles stuff was OK -- the big loser
> was atmospheric science, which was heavy on imaging. They got a lot of
> that back during Cassini's flyby, and presumably even more from New
> Horizons.
Toward the end of its mission Galileo got great close-up shots of Io's
volcanoes where you could see the lava glowing down inside the craters;
http://zuserver2.star.ucl.ac.uk/~idh/apod/ap020327.html
http://www-aig.jpl.nasa.gov/public/projects/ase/images/io_volcano.jpg
Did they ever figure out why the drop probe gave such unexpected results
during its descent into the clouds? Did it come down in a boundary
between two cloud belts as was speculated at the time?
Pat