NASA's Spirit lander is scheduled to touch down just before midnight tomorrow (Jan. 3) on Mars' Gusev Crater. It will find itself in a 200 kilometer-long depression that could have been an ancient lakebed. If indeed there was once water there, there is a very good chance of finding evidence of ancient microbial life in the dust and rocks around Gusev.
But Spirit will encounter boulders, chasms and unknown geological obstacles. That's because this time the agency let the scientists choose the landing site, rather than the mission engineers. “They've taken a much riskier option for a landing site, which means that the chances for failure are much higher,” said Christopher Chyba, a Stanford astrobiologist. “And that's exactly what they should be doing.”
When the Viking landers touched Martian regolith for the first time in 1976, the sites were chosen primarily for safety reasons. Telescopes showed the regions to be ...
