Saturn's satellite Enceladus

Saturn

. The bright, smooth surface of Enceladus, shown in this Voyager 2 image obtained on 25 August 1981, reflects almost 100 percent of the incident sunlight, making it one of the most reflective objects in the solar system. When viewed up close, part of its surface is scarred with impact craters, and such impacts might have released liquid water from the satellite's interior. Other parts of the surface contain cracks and grooves, suggesting that internal stresses that may have also discharged water that froze into smooth ice. (Courtesy of JPL and NASA.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University