|MadSci Network: Astronomy|
Missed this in my inbox... Close, but not quite, to answer your question. NASA rover prototypes aren't tested in what we would call "extremophile" environments (high temperature or acidic environments). They're tested on Earth, under Earth gravity, in similar soil environments. NASA does have soil laboratories which create artificial soils meant to match the soil conditions on Mars and the Moon for its rovers, yes, and tests them in those. To my knowledge, though, they still test in Earth atmosphere under normal temperatures and pressures. Mars has about 1% of our atmosphere's density and is made of carbon dioxide, so it's a bit different, but the soil simulation is generally sufficient to provide (especially under our higher gravitation) a very thorough test of rover operations. After all, it's usually the wheels and things in contact with the soil which give out first.
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