Is there really water on Mars?

NASA's Mars Phoenix Lander has just sent back photos of the red planet's surface. From the time astronomers first turned their telescopes on Mars, we have imagined life there. Of course, that would require the planet to contain life-sustaining water. Does it?

Until recently, most people assumed that if Mars had liquid water, it no longer did and hadn't for quite some time. Just a decade ago,… » Full Story on HowStuffWorks