Engineers Assessing Cassini Spacecraft

Engineers at NASA's Jet Propulsion Laboratory are working to understand what caused NASA's Cassini spacecraft to put itself into "safe mode," a precautionary standby mode...

Ask an Expert: Why Study Comets, Meteors and Asteroids?

What do we learn from studying comets, meteors and asteroids? On Friday, Nov. 5 from 10:00 a.m. to noon EDT, NASA expert Bill Cooke will answer your questions...

NASA EPOXI Flyby Reveals New Insights Into Comet Features

NASA's EPOXI mission spacecraft successfully flew past comet Hartley 2 at 10 a.m. EDT Thursday. Scientists say initial images from the flyby provide new information about the comet's volume and material spewing from its surface...

Thawing a Planet-Sized Snowball

The Earth has plunged into a deep freeze several times in the past, with ice covering the land and sea for millions of years...