Comparing The Planets

Water ice and water vapor can be found on some of the terrestrial planets and satellites in our Solar System. Liquid surface water is currently only found on the Earth, although evidence for ancient seas and channels exist on Mars. Data from the Galileo mission suggest a layer of liquid water may exist beneath the icy surface of Europa, one of Jupiter's satellites.
Water and Carbon Dioxide Ice Cap at Mars' South Pole 40k JPEG NASA Viking Orbiter 2 Image processed by the U.S. Geological Survey	Ice Rafting on Jupiter's Satellite Europa 102k JPEG NASA Image #PIA01127 taken by the Galieo Spacecraft

Liquid Water Dominates the Surface of the Earth 54k JPEG NASA Apollo 17 Image	Water ice may be located in this impact crater at the Lunar South Pole. 114k JPEG Clementine image courtesy Naval Research Laboratory (NRL)

Water ice may be located below the surface of mars in layers of "permafrost". 60k JPEG Image courtesy of NASA/Jet Propulsion Laboratory/Arizona State University