... Credit: Mars Exploration Rover Mission , JPL , NASA Explanation: Pictured above , the path of the robot rover Spirit on Mars can be traced far into the distance. ... Landing inside vast Gusev crater near the beginning of this year, Spirit, along with its sister robot Opportunity across the planet, has uncovered key evidence for ancient Martian water . ... Publications with keywords: Mars - water . Publications with words: Mars - water . ... Mars in View . ... A Path Into Victoria Crater on Mars . ...