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Apollo, where are they now?


Kelderek

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I thought this was cool:

Apollo CM and LM locations

Contains all of the known locations for the command modules and lunar modules (ascent stages). The CMs are all in museums, so you can use this list to see if one of them is located near enough to visit. I had no idea that there was a CM here in Atlanta, GA where I live, so now I can set up a time to go a check it out in person.

The LMs were mostly sent for a targeted impact on the moon, but I found it curious that a couple of their locations are still unknown - especially the "Eagle" from Apollo 11. We've had all sorts of orbiters mapping out the lunar surface for years I would have expected this to have been found by now. Of course it took them a while to find that "Beagle" lander on Mars. Could "Eagle" possibly still be in lunar orbit?

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I thought this was cool:

Apollo CM and LM locations

Contains all of the known locations for the command modules and lunar modules (ascent stages). The CMs are all in museums, so you can use this list to see if one of them is located near enough to visit. I had no idea that there was a CM here in Atlanta, GA where I live, so now I can set up a time to go a check it out in person.

The LMs were mostly sent for a targeted impact on the moon, but I found it curious that a couple of their locations are still unknown - especially the "Eagle" from Apollo 11. We've had all sorts of orbiters mapping out the lunar surface for years I would have expected this to have been found by now. Of course it took them a while to find that "Beagle" lander on Mars. Could "Eagle" possibly still be in lunar orbit?

The Moon has a lot of irregularities in its near-field gravitational field. These are caused by concentrations of mass just under the lunar crust ("masscons") and I think they are all associated with the lunar mares (the lava-filled impact basins). We discovered these masscons when we first started lunar exploration and found that low orbits around the Moon are not stable. So if the Eagle was left in low orbit, then the masscons would have made it crash into the lunar surface at an unpredictable spot a long time ago.

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We lost the Eagle!?

This must be rectified.

Good luck figuring out which impact crater or marking was due to the Eagle impact; you need before and after images and the "before" images taken from Earth are almost certainly not going to be high enough resolution- and that's assuming it impacted on the near side. The far side images from before 1969 are probably going to be even worse.

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Good luck figuring out which impact crater or marking was due to the Eagle impact; you need before and after images and the "before" images taken from Earth are almost certainly not going to be high enough resolution- and that's assuming it impacted on the near side. The far side images from before 1969 are probably going to be even worse.

Not to mention the 9001 other impacts have occurred on the moon since 1969.

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Not to mention the 9001 other impacts have occurred on the moon since 1969.

Yes, but the orbital plane wouldn't have changed very much before an LM left in lunar orbit would have crashed into the surface. Why? Because it takes a massive change in velocity to significantly affect the orbital plane, but only a tiny change is required to switch a low orbit into an orbit that intersects the surface. Thus, you could narrow your search down to within a narrow strip centered on the last known orbital plane, ruling out almost all of the impacts since 1969. It's probably near-to-certain that there were no natural impacts as large as the LM would have been, within that narrow strip since 1969. ADDITIONALLY, you could rule at all impacts that appeared to have come in from a high angle. The impact the LM would have made would have been a grazing impact. BUT, of course, we don't have high enough resolution "before" images.

The LRO might provide high enough resolution images to find some candidate, fresh-looking impact scars, but without before images or landing at each site, we'd never know for certain.

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The Apollo 10 LM is in a heliocentric orbit?! Awesome!

Yeah, they crashed the descent stage and fired the ascent stage into a heliocentric orbit. Nobody has yet identified it yet.

I'm kinda curious how it would look now.

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Yeah, they crashed the descent stage and fired the ascent stage into a heliocentric orbit. Nobody has yet identified it yet.

I'm kinda curious how it would look now.

I did not know this. So after they ditched the ascent stage the engine was remotely fired again? And how was the craft aligned?

"on May 23 the LM ascent stage was jettisoned into solar orbit"

How? This is actually kinda surprising to me. I was sure all of them crashed.

Edited by Motokid600
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I don't think they did it on purpose. It was probably a freak effect of the irregular masscons that make lunar orbits unstable.

Note that the early S-IVBs until Apollo 12 were abandoned on a flyby trajectory that also got them into heliocentric orbits. From Apollo 13 onwards, they purposely crashed them into the moon for sismic experiments. The Apollo 12 S-IVB actually returned into Earth orbit in 2002 and was ejected again a year later.

Edited by Nibb31
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LMs were all left in the moon orbit which is very unstable due to masscons. It decayed rapidly over days, impact points are mostly unknown - the kinetic velocity isn't that large, the impact would be difficult to observe even if it is on the visible side at all.

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I did not know this. So after they ditched the ascent stage the engine was remotely fired again? And how was the craft aligned?

"on May 23 the LM ascent stage was jettisoned into solar orbit"

How? This is actually kinda surprising to me. I was sure all of them crashed.

The landing crew performed a descent burn to test the descent stage. Then they ditched the descent stage and used the ascent stage to get back into orbit again. After the crew was back in the csm they remotly fired the ascent stage into a heliocentric orbit. I am not sure why they did that.

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The landing crew performed a descent burn to test the descent stage. Then they ditched the descent stage and used the ascent stage to get back into orbit again. After the crew was back in the csm they remotly fired the ascent stage into a heliocentric orbit. I am not sure why they did that.

Probably to test the ascent stage's reliability.

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I'm surprised the ascent stage had the ability to point prograde on its own and fire the engine.

The LM had the same PGNCS as the CM. All they needed to do was to program the AGC before jettisonning the LM and then send an execute signal from the CM.

It still seems like a lot of effort for not much return. The Apollo 10 ascent stage wasn't fully fueled anyway, so it didn't provide a very accurate endurance test of the ascent engine.

Maybe they just wanted to get it out of the way to be sure that it wouldn't interfere with future missions.

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