Erosion has exposed eight ice sites, some as shallow as a few feet (one meter) below the surface, and going as deep as 100 meters or more, it said. These underground cliffs appear "to be nearly pure ice," said the report, which is based on data from the Mars Reconnaissance Orbiter, launched in 2005.
"This kind of ice is more widespread than previously thought," said Colin Dundas, a geologist at the US Geological Survey in Flagstaff, Arizona.