Regolith of small asteroids formed by thermal fatigue

The centimeter-sized fragments and smaller particles that make up the regolith — the layer of loose, unconsolidated rock and dust — of small asteroids is formed by temperature cycling that breaks down rock in a process called thermal fatigue, according to a paper published today in the Nature Advance Online Publication.

Could alien soils make spacecraft heat shields?

NASA scientists will next week test whether a heat shield made from the soil of the moon, Mars or an asteroid could stand up to a plunge through Earth's atmosphere.