Ancient stream bed on Mars

Curiosity has been on Mars for 51 sol-days and today NASA announced it has found what looks like a concrete slab made up of rounded stones which is probably an ancient stream bed formed by hip-deep fast-moving water over thousands or millions of years. Observers have long hypothesized the canyons and river-like beds photographed from space were carved by water, but only now do researchers have on-the-ground confirmation for the first time.
posted by stbalbach on Sep 29, 2012 - 71 comments