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Unmanned Spaceflight.com > Earth & Moon > Lunar Exploration
As old as Voyager
Could the disturbance marked 'B' on the Clementine image accompanying this article be the impact site of the Apollo 15 LM?

http://www.space.com/missionlaunches/missi...tos_010427.html

The impact site for the Apollo 15 LM is known to be at 26.36 N 0.25 E, so it fits with the image pretty well.

If this is the impact site I think all the dark patch shows is ejecta with the actual crater being too small to resolve. The larger crater amidst the dark area cannot be the LM impact crater as it appears in Apollo 15 images.
Phil Stooke
No, I'm afraid not. Go to:

http://www.lpi.usra.edu/meetings/lpsc2001/pdf/1075.pdf

to see the original report, where the feature B is revealed as an ordinary crater, and much too large to be made by Apollo hardware. The Apollo 15 LM ascent stage impacted further west in the hilly area adjacent to Archimedes crater. I have looked at Clementine images in this area but nothing unusual shows up.

Phil Stooke
As old as Voyager
Thanks Phil, I was rather dubious that it was a fresh crater but thought I'd check. Lets hope LRO can spot the Apollo 15 LM impact site.
Phil Stooke
I goofed and put a pic of this in the LRO imaging thread.

Phil
As old as Voyager
The impact site of the Apollo 17 LM Ascent Stage should be pretty conspicuous.

http://www.hq.nasa.gov/alsj/a17/a17.labeled.TL.jpg

Does anyone know if a study of Clementine images has shown the impact site? I've had a look at the 2005 Hubble image of Taurus-Littrow but the resolution isn't high enough.

You'd think that slamming the Ascent Stage into the massif at a low angle would create a big bright streak at the point indicated in the linked image.
kenny
You know, they tried to film the Apollo 17 ascent stage impact with the TV camera on the Rover, which was still working. If you look at the TV clips they were zooming in and out and scanning aorund too much and missed it. If they'd kept it wide angle and at a fixed viewing direction, they'd have had a good chance of seeing the impact event and ejecta, I think.
Phil Stooke
I (and others) have looked for the Apollo 17 LM AS site in Clementine, HST and the new radar images, with no luck. It will have to wait for the new generation of orbiters.

Phil
edstrick
Note that non-hypervelocity impacts, like LM ascent stages, S-IVB's, Rangers, and assorted Soviet stages and failed probes, generate little highly pulverized fresh rock debris and mostly re-arrange regolith. The result, in impacts that have been identified, is dark ejecta, like astronaut-disturbed soil, not bright crater rays.
dvandorn
I hate to disagree with your reasoning, Ed, but I do. Astronaut bootprints and otherwise disturbed soils only appeared dark in the immediate vicinity of the LMs, where the descent engine plumes had swept loose dust from the surface and brightened it. Every LM landing site imaged by the J-mission pancams showed a brightened "splash patch" of soil extending 50 or so meters out from the actual landing points.

Extensive review of the TV and film record, and accounts of the astronauts' impressions on the scene, confirm that footprints, rover tracks, etc., did not generally darken the soils at any reasonable distance from the LMs. In fact, in some places (especially at highland sites), footprints and other soil disturbances actually brightened the soil, since in some areas a dark gray surface covered brighter deposits.

That said, some hardware impact sites that have been imaged do display dark rays -- notably some of the S-IVB craters. I've wondered if that might not have something to do with the composition of the impactors, however... rolleyes.gif

-the other Doug
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