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[akuo]

Heatshield AHOY!

:-)

[Guest_BruceMoomaw_*]

Opinions seem to vary on whether the Genesis samples are scientifically retrievable. The team itself is insisting that many of the collectors for oxygen and nitrogen isotopes in the solar wind -- the top two science goals of the mission, by far -- are indeed retrievable, and that the same may be true of many of the lesser goals (such as noble gas analysis). Others -- such as SpaceDaily's professional curmudgeon Jeffrey Bell -- say that, since the solar wind atoms are embedded only 1/50 of a micron deep in the collector plates (that's less than 1 millionth of an inch) and the latter were exposed to atmosphere, humidity and dust, no scientist in his right mind will trust the results. However, I've talked personally with Donald Brownlee -- the PI for the Stardust comet-dust retrieval mission -- and he thinks that it may very well be possible to adequately clean the top surfaces of the collector plates of contamination without removing such shallowly embedded solar wind atoms; as he points out, anyone who washes a glass window with a non-abrasive substance routinely does just that. So, until I learn more, I reserve judgment.

Brownless, by the way, also says that an examination of the construction records for the Stardust capsule make it pretty certain that the upside-down parachute switch error in the Genesis capsule has not been repeated for the Stardust capsule -- but he also says that, since the dust grains in Stardust are embedded 1 to several cm deep in a sheet of relatively nonbrittle aerogel, they are more likely to come through a crash in scientifically acceptable shape, unless the capsule crashes onto the salt flats after the latter have been recently rained on. However, finding and retrieving the capsule quickly would be vital -- and the Stardust capsule will land at night.