The recent discussions on the analysis of the bits of Surveyor 3 that Apollo 12 brought back have been interesting. I never knew about of the vidicon tube being vaporized!

I have seen precious little info on pieces of vehicles that have been brought back to Earth after long exposure to space. For example, what did we learn from the L-DEF (Long-Duration Exposure Facility) that orbited Earth years longer than intended, because of the Challenger accident?

Also, a friend of mine was an engineering lead on the early Hubble Space Telescope repair missions. I talked to him briefly after they had looked at some of the pieces of HST brought back from the servicing missions. He said that there were fasicnating - and at the time, unexplained - effects on the metal of the spacecraft at a micro level. He couldn't go into more detail because the results hadn't been made public yet. And I have never heard any more about this. Does anyone know of such an analysis?

Of course there were also macro-level effects on Hubble, too - remember the hole punched in one solar panel from orbital debris?

The LDEF was certainly rather battered after it's unexpected time in space (comparable to some ISS components but much less than HST). Apart from micrometeoroid impacts (natural and artificial) satellites can suffer from strange erosive effects from atomic oxygen, too - and Solar UV is no fun, either!

Bob Shaw

A material science investigation of the Pioneers or Voyagers (sorry, but Galileo is zorched!) would be fascinating (not that their retrieval is much more likely than Galileo's). The intense radiation damage and long exposure to CMEs, solar UV, cold and vacuum must have really done some damage.

And perhaps some materials have fared better than we expect, too.

Has anyone considered radiological damage (causing enhanced outgassing, perhaps) of the Pioneer spacecraft materials as a possible expalnation of the 'Pioneer effect' ?

Another thread has had a lot of more deserved, somewhat less undeserved ESA PR-effort bashing, but there and probably elswhere, I've done a fair share of NASA PR-office bashing (mostly of the <expletive deleted> schedule poster(s) for NASA-TV.

One area that is beyond pathetic is NASA publication and press-releasing of *ENGINEERING* SCIENCE results. LDEF, Thethered Satellite missions (granted that both were aborted incomplete), other sample retrievals, etc., plus materials and physics (and to a lesser extent biomed) science payloads on Spacelab and Spacehab shuttle missions. I expect a considerable amount of significant and interesting science has resulted from these efforts, but there's a near total lack of NASA tooting it's own horn on the results.

Granted that the price per published paper is probably 1000 or some such number as science papers resulting from antarctic or deep-sea-submersible science, casting doubt on the value of what we're getting, but unless I'm reading terminally specialized enginering and materials science journals that have these results (and I'm not), don't blame me for incorrectly concluding we're getting nothing for our $.

Online Hughes Aircraft Company document here.

Surveyor 3 Parts and Materials/Evaluation of Lunar Effects Returned from the Moon by Apollo 12 - Submitted January 22, 1971:

http://ntrs.nasa.gov/archive/nasa/casi.ntr..._1971008092.pdf