That means the Pathfinder's six-wheeled, 23 pound buggy named Sojourner will have to wait till the Martian morrow before it rolls out and begins to sniff around the red planet. Scientists said they will send it out to rocks that look promising. Not the typical red dust covered, lifeless looking Martian rock, but maybe something darker that would suggest that there was life sustaining water on the planet. While Sojourner will spend at least a week traversing the Martian terrain, taking pictures and analyzing soil and minerals - before it possibly runs out of energy - the main craft itself will spend a minimum of a month taking pictures and studying the atmosphere and weather. Scientists believe Ares Vallis is an area through which torrents of water flowed through during catastrophic floods aeons ago. They hope the Sojourner's alpha proton X-ray spectrometer can determine the mineral content of nearby rocks so that they can assess if the planet was one a warmer, wetter place where microbial life could have developed.