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Unmanned Spaceflight.com > Earth & Moon > Lunar Exploration > LRO & LCROSS
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ilbasso
QUOTE (ugordan @ Jul 16 2009, 01:43 PM) *
Via NSF.com:

MEDIA ADVISORY: M09-133

NASA BRIEFS MEDIA ON NEW IMAGES OF APOLLO LUNAR LANDING SITES
...


First of all, maybe this was supposed to be nsf.gov, not .com.

There's nothing on that website or the LROC website about this that I could find. Maybe it was pulled?
Phil Stooke
Presumably NASA Space Flight, not National Science Foundation!- though I don't see the announcement on that site.

But see it here:

http://www.nasa.gov/news/media/newsaudio/index.html

Phil
mcaplinger
QUOTE (jmknapp @ Jul 16 2009, 12:21 PM) *
In the July 15th space.com article referenced upthread, I guess they were sandbagging a little as the photos must already have been taken several days before.

Though the article doesn't say, I'm fairly sure that interview occurred before the images were taken, if not before the launch of LRO, and probably refers to expected image quality from 50 km. From a higher altitude the resolution will obviously suffer.
Paul Fjeld
I agree. Robinson was talking before they got anything - no sandbagging. But assuming 1.2 meter/pixel at the 120km altitude, the LM Descent Stage and its shadow should be defined by no less than 70 pixels. It should be REALLY obvious and I bet you'll make out the other little bits. I'm hoping they'll say "here is the '11 site... oh yah, and here are the rest!"
jmknapp
QUOTE (mcaplinger @ Jul 16 2009, 10:05 PM) *
Though the article doesn't say, I'm fairly sure that interview occurred before the images were taken, if not before the launch of LRO, and probably refers to expected image quality from 50 km. From a higher altitude the resolution will obviously suffer.


Ah, that makes sense as the current altitude crossing the equator (per Paul F.) is about 120 km.
Zvezdichko
Well, this will still allow us to see something
djellison
QUOTE (Paul Fjeld @ Jul 17 2009, 03:25 AM) *
But assuming 1.2 meter/pixel at the 120km altitude, the LM Descent Stage and its shadow should be defined by no less than 70 pixels.


The LEM is approx 4.5 metres across. At 1.2m/pixel - that's 3-4 pixels across, a total of perhaps 16 pixels of LEM.

Assuming a height of 4 meters ( which is generous) - and illumination at 10 degrees - the shadow will be another 17 or so pixels long.

Doug
Paul Fjeld
Your calculations are close. The LM structure is 4.22 m across, but footpad edge to footpad edge (still bright Kapton?) is 9.45 m. I would add the gear to show up as another pixel at least making the LM 25 pixels (5 ^2). The top of the LM Descent Stage structure is 3.18 m but the tops of the plume deflectors are at 4.23 m. So the shadow trig has it from 18 to 20 meters long. So 17 or slightly fewer pixels not squared but maybe a third of that is at least 75 pixels. So I revise my estimate upwards: the LM will be defined by at least 100 pixels.

Then there will be extra flotsam like the brightly lit backpacks and other things. We'll know soon!

EDIT: of course I'm neglecting slant range: this all assumes LRO was nearly right above the site when the pic was taken.
djellison
Oh - ok - you were counting ALL the pixels. Anyway - I started a new LRO thread for Apollo sites - we'll need it in about an hour or two hopefully smile.gif
jmknapp
QUOTE (Paul Fjeld @ Jul 17 2009, 10:30 AM) *
EDIT: of course I'm neglecting slant range: this all assumes LRO was nearly right above the site when the pic was taken.


Since the ground tracks on successive passes are about 30 km apart, and the vantage point is 120 km high, I suppose there needn't be much slant (15/120 = 7 degrees).
glennwsmith
John Moore, thanks for link to details on Arecibo radar mapping of the Moon's poles. So, there was no magic involved -- Arecibo had the same oblique view that we do, and as a result was only able to examine 25% of the craters' permanently shadowed areas -- and obviously not the deepest areas. Thus, as someone else mentioned, there is still hope that real "hit it wth a pickaxe" ice can be found on the moon -- lunar gold!
John Moore
Re: Arecibo + radar.

Glenn, you're welcome...had been reading up on it just a week earlier, so it was close to hand smile.gif

John
Zvezdichko
Uh... what happened to the other thread?
Phil Stooke
Yes, I was wondering that... but it's back now...

Phil
glennwsmith
Given that the main goal of LCROSS is to search for water ice at the moon's south pole, I suppose this is an appropriate place for the following comment, namely, that the success of said search -- and I am not predicting here that it will be successful -- will pretty much end the Mars vs. Moon debate in respect to which of the two receives our next big push. But that becomes another topic for another time and place . . .
Paul Fjeld
QUOTE (jmknapp @ Jul 10 2009, 03:26 PM) *
I made an animation of the LRO passes over the Apollo 11 site, using the "mission baseline v8" data given at http://lroc.sese.asu.edu/downloads.html.

They updated the file to v10. It looks like it tracks pretty closely with the imaging data now.
jmknapp
QUOTE (Paul Fjeld @ Aug 5 2009, 06:55 AM) *
They updated the file to v10. It looks like it tracks pretty closely with the imaging data now.


I downloaded the v10 files and indeed it tracked well, differing from the position given by http://lroc.sese.asu.edu/whereislro/ by only a few minutes. BTW, the "Where is LRO" site now seems to be gone (check link). So the question becomes "Where is Where is LRO?"

I hear that up-to-date SPICE kernels are provided to the various centers on a daily basis but those aren't available to the public. That contrasts to, say, MRO, where updated files are continually posted to the NAIF public website, including both planned and as-flown instrument pointing files (so-called CK kernels). Cassini also does this. My understanding is that the older programs (particularly Cassini, being an old-school big budget project) were more committed to this. In Cassini's case, they even provide "science plan" kernels containing text information about the type and purpose of observations, correlated with instrument command sequences.

Eventually the pointing and trajectory files will be posted to the PDS, but only after 8 months or something like that. So near real time for LRO looks to be a no go, as far as the public is concerned.
Paul Fjeld
I have no idea how much effort it takes to keep going something like "Where is LRO." I would think it would be trivial: just point some telemetry or tracking data at an automatic web thingy and off you go.

I wish NASA would, as a matter of course, maintain an up to date data stream of a mission's state vector and attitude. They could have a standard web protocol and each mission's data folks would plug those 9 numbers in with a time stamp (every minute or second) and we could all do with it what we wanted. We would know where pics were taken from instantly and, where there are interesting mission events, simulate them if we have the skill or interest. Planetariums could fly along with some missions - landers would be especially fun to follow in "real" time.
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