Earth's magnetic field, which shields our planet from particles streaming outward from the sun, often develops two holes that allow the largest leaks, according to researchers sponsored by NASA and the National Science Foundation.
Recent Cassini spacecraft flybys of Titan have revealed new information about possible ice volcanoes on the small moon.
The closer scientists look at Saturn's small moon Enceladus, the more they find evidence of an active world.
A 2006 solar flare surprised scientists by behaving in unexpected ways.
NASA's Cassini captured this stunning mosaic as the spacecraft sped away from Enceladus, a geologically active moon of Saturn.
During two close flybys of Saturn's moon Enceladus in 2008, the cameras on NASA's Cassini acquired several very high-resolution images of specific regions of the south polar terrain.
NASA's Mars Reconnaissance Orbiter has completed its primary, two-year science phase.
The NASA/JPL Epoxi spacecraft fired its engines today to prepare for a Dec. 29 Earth flyby. The Epoxi mission is scheduled to fly past comet Hartley 2 in 2010.
The Tarantula Nebula produces intense radiation and searing winds of multimillion-degree gas.
Climate cycles persisting for millions of years on ancient Mars left a record of rhythmic patterns in thick stacks of sedimentary rock layers.