Did an ancient Martian civilization leave clusters of reactors capable of terraforming Mars buried deep below the planet's surface, waiting for Arnold Schwarzenegger to set them off? Probably not, but NASA has just found one of the key elements of life on the red planet: liquid water. New photos taken by the Mars Global Surveyor satellite show "bright new deposits" in two Martian gullies. NASA says the appearance of those deposits suggests water has carried sediment through the gullies some time during the past seven years. Water ice and water vapor have already been spotted on Mars, but according to NASA Mars Exploration Program Lead Scientist Michael Meyer, "These observations give the strongest evidence to date that water still flows occasionally on the surface of Mars." Michael Malin of Malin Space Science Systems also believes that "these fresh deposits suggest that at some places and times on present-day Mars, liquid water is emerging from beneath the ground and briefly flowing down the slopes. This possibility raises questions about how the water would stay melted below ground, how widespread it might be, and whether there's a below-ground wet habitat conducive to life. Future missions may provide the answers."