sciencehabit writes from a report via Science Magazine: Scientists have discovered eight cliffs of nearly pure water ice on Mars, some of which stand nearly 100 meters tall. The discovery points to large stores of underground ice buried only a meter or two below the surface at surprisingly low martian latitudes, in regions where ice had not yet been detected. Each cliff seems to be the naked face of a glacier, tantalizing scientists with the promise of a layer-cake record of past martian climates and space enthusiasts with a potential resource for future human bases. Scientists discovered the cliffs with a high-resolution camera on the Mars Reconnaissance Orbiter, revisiting the sites to show their subsequent retreat as a result of vaporization, and their persistence in the martian summer. The hunt should now be on, scientists say, for similar sites closer to the equator. The findings have been reported in this week's issue of Science.