Location of Large Subsurface Water-Ice Deposit in Utopia Planitia, Mars

Diagonal striping on this map of a portion of the Utopia Planitia region on Mars indicates the area where a large subsurface deposit rich in water ice was assessed using the Shallow Radar (SHARAD) instrument on NASA's Mars Reconnaissance Orbiter. The area is about halfway between the planet's equator and north pole, and the deposit is estimated to hold about as much water as what is in Lake Superior, largest of the Great Lakes. The scale bar at lower right indicates 140 kilometers (76 miles). The violet vertical bars show depth to the bottom of the ice-rich deposit, as estimated from SHARAD passes overhead. Darkest violet indicates a depth of about 550 feet (about 170 meters). Palest violet indicates a depth of about 33 feet (10 meters). The value of 2.8 plus-or-minus 0.8 in the upper right corner denotes the dielectric constant, a property related to radar reflectivity. The value of 14,300 cubic kilometers is an estimate of the volume of water in the deposit. http://photojournal.jpl.nasa.gov/catalog/PIA21138