change the date of launching the mission LRO / LCROSS

[valmirmmorais]

Dear Friends:

I inform you that NASA, in internal memo by Craig Tooley, LRO project
manager notified the change of date of launching the mission LRO /
LCROSS.

The next set of LRO/LCROSS launch days opens on 5/7/2009.

Link: http://www.spaceref.com/news/viewsr.html?pid=30599

thanks,

Valmir Martins de Morais

Estação Astronômica PieGise
Latitude = 07º 12' 27.378" S
Longitude= 39º 18' 48.586" W
Altitude = 400,2 mts.
Juazeiro do Norte, Ceará - Brasil

[cano...@yahoo.com]

There are no LRO or LCROSS press releases on this matter, but the
Kennedy Space Center launch calendar now also shows LRO for launch on
May 7.

http://www.kennedyspacecenter.com/events.aspx#2009/5/0/

Click "rocket launch" to display.

- Kurt

On Feb 12, 6:16 pm, valmirmmorais <valmirmmart...@gmail.com> wrote:
> Dear Friends:
> I inform you that NASA, in internal memo by Craig Tooley, LRO project
> manager notified the change of date of launching the mission LRO /
> LCROSS.
> The next set of LRO/LCROSS launch days opens on 5/7/2009.

<snip>

[cano...@yahoo.com]

> http://www.kennedyspacecenter.com/events.aspx#2009/5/0/

P.S. - The above link is to the Kennedy Space Center Visitor's center
which is run by a private contractor for NASA. The "official" NASA
launch schedule, still shows April 24, but I assume that this is just
an updating delay:

http://www.nasa.gov/missions/highlights/schedule.html

- Kurt

[Arnold Ashcraft]

Kurt:
With a latitudinal libration of +7 degrees 25 minutes, they must be
going for the north polar targets. That makes the imaging over the
next couple of days pretty important. We have been having severe
winds in New Jersey (I didn't dare to open up my observatory last
night) but it has finally calmed down. Seeing is expected to be poor
tonight. I hope that folks with better seeing are doing their
imaging tonight and the next few nights. I was able to get an image
night before last, but the seeing was really bad and I am not at all
pleased with the results. Hoping it is better tonight. At least
it's clear and I don't have to worry about my observatory roof flying
away.
Clif

[cano...@yahoo.com]

> With a latitudinal libration of +7 degrees 25 minutes, they must be
> going for the north polar targets.

That is my reading of the LCROSS chart that Jim Mosher posted - that
northern targets remain more likely than southern for a May 7 launch
date. Jim may have a different reading. However, we really will not
know until a further announcement is made, probably at launch. So,
I'm not putting any more energy into reading teas leaves on that
topic. Once launch occurs and they hit the first gravity assist turn
into cruise orbit, then the north or south issue will be set in
stone. To hit the north pole, one would have to turn towards the
south ecliptic pole on the gravity assist pass; to the hit the south
pole, one would have to turn towards the north ecliptic pole. I
understand that there is some play in the fuel budget during the
cruise orbits to speed up or slow down the orbital speed and thus
further refine specific crater targeting. This is consistent with the
idea that LRO goes straight to the Moon and there are three or four
months for LRO to search for indications of ice layers at the poles
with its advanced remote sensing equipment.

At 3:00am, I got up and played around getting my imaging equipment
working again with the now repaired 4" scope. Grabbed some north
polar avi's last night but was throttled by exceptionally bad
seeing.

The Moon is crossing the ecliptic low-end of the zodiac in Sgr - or as
I call the "zodicial seeing pit" Additionally, since the Moon's orbit
axis is tilted with respect to the ecliptic, it's orbital tilt can
place it further below the ecliptic. Currently that is happening and
this puts the Moon at an extraordinary low altitude.

This geometry will continue through 3rd and 4th qtrs and into the New
Moon. By Feb. 26, the crescent Moon will cross to the north side of
the ecliptic and into that part of the ecliptic (Psc through Tau) that
results in high local altitudes.

Nonethess, I need to practice with my gear, so I'll probably be
getting up early in the morning to grab what can be grabbed.

Clear Skies - Kurt

On Feb 13, 6:13 pm, Arnold Ashcraft <wa2...@optonline.net> wrote:
> Kurt:
>         With a latitudinal libration of +7 degrees 25 minutes, they must be  
> going for the north polar targets.  That makes the imaging over the  
> next couple of days pretty important.  We have been having severe  
> winds in New Jersey (I didn't dare to open up my observatory last  
> night) but it has finally calmed down.  Seeing is expected to be poor  
> tonight.  I hope that folks with better seeing are doing their  
> imaging tonight and the next few nights.  I was able to get an image  
> night before last, but the seeing was really bad and I am not at all  
> pleased with the results.  Hoping it is better tonight.  At least  
> it's clear and I don't have to worry about my observatory roof flying  
> away.
>                                                 Clif

> On Feb 13, 2009, at 6:16 PM, canopu...@yahoo.com wrote:
>
>
>
>
>
> > There are no LRO or LCROSS press releases on this matter, but the
> > Kennedy Space Center launch calendar now also shows LRO for launch on
> > May 7.
>
> >http://www.kennedyspacecenter.com/events.aspx#2009/5/0/
>
> > Click "rocket launch" to display.
>
> > - Kurt
>
> > On Feb 12, 6:16 pm, valmirmmorais <valmirmmart...@gmail.com> wrote:
> >> Dear Friends:
> >> I inform you that NASA, in internal memo by Craig Tooley, LRO project
> >> manager notified the change of date of launching the mission LRO /
> >> LCROSS.
> >> The next set of LRO/LCROSS launch days opens on 5/7/2009.

> > <snip>- Hide quoted text -
>
> - Show quoted text -

[Jim Mosher]

On Feb 13, 5:13 pm, Arnold Ashcraft <wa2...@optonline.net> wrote:

> With a latitudinal libration of +7 degrees 25 minutes, they must be
> going for the north polar targets.

Clif -

It sounds like you are quoting the librations for a northern
hemisphere observer on the launch date. What matters, of course, are
the librations at the moment of impact, which can be quite different.

According to the planning chart provided by Dr. Heldmann, posted in
this group towards the end of the "Questions Answered by LCROSS
Scientists" at:

http://groups.google.com/group/lcross_observation/web/questions-answered-by-lcross-scientists#16

Or directly at:

http://lcross_observation.googlegroups.com/web/HeldmanEmail_2009Feb11_ImpactDates_Picture_10.GIF?gsc=6KxBLBYAAACQc795rV66x54SMPN--gylg-kXU5InE09W2o0GCSVgCQ

A May 7, 2009 launch date might result (among other possibilities) in
an impact on Aug 2, Aug 15, Aug 28, Sep 11, Sep 24, or Oct 8 (each +/-
1 day). For 12 UT in Hawaii, on the dates stated, the libration in
latitude would be +3.7, -4.4, +4.9, -4.7, +4.8, -4.9 deg.

The Aug 15 date has been preliminarily shaded as "bad phase" -- with
an elongation of about 67 deg, giving illumination of 31%, the Moon is
a bit closer to the Sun than desired. But that could change, since 12
UT on Aug 14 would be well within the mission parameters (42%
illuminated), and the reasons for demanding a 75 degree (or larger)
elongation may not be strong. However, if Aug 14/15th (or one of the
other dates with southerly librations) were selected, the south polar
illumination would be from the Cabeus/de Gerlach side of the pole
rather than the Shoemaker/Faustini side, which is not the kind of
illumination we've been focusing on so far.

At the moment, an Aug 28 impact, with a north polar target, has been
circled as the preferred choice for a May 7 launch; but another
consideration is the Sun's latitude on the Moon. Conditions would be a
bit "wintry" at the Moon's north pole on Aug 28, with the Sun already
0.9 deg south of the equator, and heading towards a maximum southerly
latitude of -1.55 deg on around October 26, giving rather long shadows
and unfavorable sun angles at the north pole. The importance of the
Sun's latitude will be different for different target choices and
dates, but assuming one wants the strongest lighting possible on a
target very close to the pole, a south polar impact on one of the
other dates might still be preferred.

The choice of what is a "favorable" libration also sounds like it may
be a difficult call for the mission scientists to make. At first
blush, it might seem obvious one wants the target area tilted strongly
towards Earth, but that creates the complications that if the plume is
large its upper parts might have to be observed rising in front of a
more distant sunlit wall (as we have seen would be the case with
Faustini), and for the most sensitive instruments there may be a
background of Earthshine and ambient light on the dark-appearing
crater floor that will have to be subtracted from observations of the
lower parts of the plume. There might be something to be said,
therefore, for a geometry in which the plume rises purely into the sky
above the sunlit foreground crater rim; but that would block from view
the lowest and densest parts of the sunlit plume, and would preclude
any possibility of seeing the impact flash (which might be hidden from
view by the transient crater, anyway, even if it were nominally in the
line of sight). I'm not sure what they will decide.

-- Jim

[Jim Mosher]

On Feb 13, 6:49 pm, "canopu...@yahoo.com" <canopu...@yahoo.com> wrote:

> To hit the north pole, one would have to turn towards the
> south ecliptic pole on the gravity assist pass; to the hit
> the south pole, one would have to turn towards the north
> ecliptic pole.

Kurt -

See Question 3 in the LCROSS FAQ (and the reference cited there):

http://groups.google.com/group/lcross_observation/web/lcross-faq#3

This is a small point, and I could be wrong, but I believe there are
two kinds of orbital plans: one in which the impact occurs an integral
number of orbits (months) after the swing-by, and one in which impact
occurs after a half-integral number of orbits. In the former, a swing-
by that leaves LCROSS heading towards the north ecliptic pole will
result in an impact at the south pole (after N full orbits). In the
latter, a very similar swing-by would put LCROSS on a path to strike
the north pole (after N + 0.5 orbits). The current preferred plan for
a May 7 launch and north polar impact after 3.5 months would seem to
call for LCROSS passing under the Moon's south pole and being
deflected towards the north ecliptic pole.

-- Jim

[Arnold Ashcraft]

Jim:
Thanks for the clarification. I didn't realize the thing could be
"parked" in orbit that long. From what you say, we should also do
imaging under less favorable librations, like small negative
librations for the south and small positive librations for north to
give some views of possible landmark and points upon which to guide
the big scopes when the target area is close to the limb.
Clif

[Derek C Breit]

giving rather long shadows and unfavorable sun angles at the north pole.

---------------------------------
Unfavorable is in the eye of the beholder, imo.

I think, rather than unfavorable, this is rather ideal..

Impact away from a bright area, and the plume rises a km or two and hits
sunlight..

If impact is in a highly lit area, the chances of seeing anything diminishes
drastically..

Derek

[Derek C Breit]

The Aug 15 date has been preliminarily shaded as "bad phase" -- with an
elongation of about 67 deg, giving illumination of 31%, the Moon is a bit
closer to the Sun than desired. But that could change, since 12 UT on Aug 14
would be well within the mission parameters (42% illuminated)

__________

Not only that, but _alot_ of people would already be out with scopes and
video equipment timing occultations of the Pleiades in the hours before
hand..

Assuming DST.. See attached image.. If it goes thru email..

Derek

[Jim Mosher]

On Feb 14, 11:48 am, Arnold Ashcraft <wa2...@optonline.net> wrote:

> I didn't realize the thing could be
> "parked" in orbit that long.

From a physics standpoint, I presume the lunar swing-by could be
planned in such a way as to give an impact years in the future,
although possibly a bit of extra fuel might be needed to keep it on
course in such a scenario. The main practical constraint that I glean
from the LCROSS presentations is that NASA has balked at paying the
science team to remain on standby for more than about 4 months. So
they are trying to plan something that can be completed in 120 days,
or less.

> From what you say, we should also do imaging
> under less favorable librations, like small negative
> librations for the south and small positive librations
> for north to give some views of possible landmark and
> points upon which to guide the big scopes when the
> target area is close to the limb.

The possibility that the target area might not be strongly librated
onto the visible disk is a speculation on my part. There is nothing
in the LCROSS presentations to suggest they are planning such a
thing. Nonetheless a reference atlas of the poles such as Kurt is
planning, or something similar to it, sounds like a valuable thing in
its own right, and the NASA request on which it is based refers simply
to wanting Earth-based images with a variety of lightings and
librations. Among other things, this will help to verify the accuracy
of things like the new digital elevation maps of the poles (that Derek
has pointed out) recently announced by the Kaguya scientists:

http://groups.google.com/group/lcross_observation/msg/da91fec23c3d421d

In addition to "unfavorable" librations, views closer to Full Moon
than the current matrix allows also seem valuable to me. The NASA
scientists say they are interested in distinguishing albedo
(reflectance) variations from lighting variations, and that Full Moon
is when albedo differences (typically rather small) are most
apparent. The combination of Full Moon lighting and a pole tipped
towards Earth also helps to clarify the topography by outlining the
far sides of the ridge tops with shadow in a more uniform way than can
be seen at other phases.

-- Jim

[Jim Mosher]

On Feb 14, 12:06 pm, "Derek C Breit" <breit_id...@hotmail.com> wrote:

> Unfavorable is in the eye of the beholder, imo.
>
> I think, rather than unfavorable, this is rather ideal..
>
> Impact away from a bright area, and the plume rises a km
> or two and hits sunlight.

I completely understand your point of view, Derek; but it might be
helpful to keep in mind that the estimates of how much dust the LCROSS
impact will loft into the "air", and how high it will go, are highly
speculative. The only thing that is certain is that the cloud will be
denser closer to the surface.

Also, the Earth-based observational campaign is something of a value-
added extra. The main intent of the mission is to observe the impact
from overhead using instruments on the Shepherding Spacecraft, and
possibly LRO. After photographing the thermal flash, the LCROSS
instruments will be looking for the spectral signature of whatever
debris reaches the sunlight over the impact site. To maximize the
chance of seeing something, I assume the scientists want a geometry in
which sunlight reaches as close as possible to the crater's shadowed
floor, so that the lowest and densest possible parts of the cloud will
be illuminated.

That calls for the Sun to be as high in the sky as possible as seen
from the point of impact. For a crater on the central meridian, the
highest solar elevation occurs near Full Moon; for one at 90 deg east
or west it occurs near First or Last Quarter; and for all positions,
the Sun is highest at the season of the year when it is closest to the
pole in question. As much as Earth-based observers might wish to see
a bright plume against a dark background, the long shadows and greater
darkness that occur at the opposite season mean the sunlight is not as
close to the surface as it could be; and hence it is a "less
favorable" situation for the primary mission.

-- Jim

[cano...@yahoo.com]

Thank you for taking the time to post this here and in other
interested news groups. - Kurt

On Feb 12, 6:16 pm, valmirmmorais <valmirmmart...@gmail.com> wrote:

> Dear Friends:
>
> I inform you that NASA, in internal memo by Craig Tooley, LRO project
> manager notified the change of date of launching the mission LRO /
> LCROSS.

<snip>

[valmirmmorais]

Dear Kurt,

I would like to express more in the group, participate more,
unfortunately not master the English language. Use translators to
follow the procedures for obtaining images, ideas, experiences and
guidelines for the observations of the impact. The amateur astronomers
around the world would benefit from what is said here, with all the
beautiful work done by you all of the group.

I hope the translator to express what I say with certainty.

Valmir.

[cano...@yahoo.com]

Valmir,

My Spanish or Portuguese is much worse than your English! I have
found online translators to be useful to communication across language
barriers.

http://www.freetranslation.com/

You should feel free to communicate in your native, assuming it is
supported by an online translator.

Welcome, Kurt

===============
English to Spanish Auto Translation

¡Mi español o Portuguese son mucho peor que su inglés! He encontrado
traductores que en línea para ser útiles a la comunicación a través de
barreras de idioma.

http://www.freetranslation.com/

Usted debe sentirse libre comunicar en su nativo, asumiendo que es
apoyado por un traductor en línea.

La bienvenida, Kurt

================
English to Portuguese auto translation

Meu espanhol ou Portuguese é muito pior que seu inglês! Achei
tradutores on-line ser útil a comunicação através de barreiras de
linguagem.

http://www.freetranslation.com/

Deve sentir-se livre para comunicar em seu nativo, supondo-o é apoiado
por um tradutor on-line.

As boas-vindas, Kurt

=================