... Tonight's Sky . ... SUN MOON MERCURY VENUS MARS, JUPITER SATURN . ... Trapped Mars rover finds evidence of subsurface water . ... The ground where NASA's Mars Exploration Rover Spirit became stuck last year holds evidence that water, perhaps as snow melt, trickled into the subsurface fairly recently and on a continuing basis. ... These newest Spirit findings contribute to an accumulating set of clues that Mars may still have small amounts of liquid water at some periods during ongoing climate cycles...