Explore astronomy, from the latest trip to the International Space Station to alien planets outside our solar system.
Galaxy is believed to have existed 480 million years after the Big Bang.
The photo contest requires its amateur astronomers to first find the solar sail and then submit their best images.
Astronomers say they have an image of what may be the oldest galaxy ever seen, a starry cluster that came into being when the Universe was a baby.
NASA educator astronaut Barbara Morgan reflects on the space shuttle Challenger accident 25 years ago that killed America's first teacher astronaut, Christa McAuliffe.
On the 25th anniversary, a look back at the tragic space mission that transformed NASA.
Part 2 of a series exploring the cosmos from the perspective of Vatican astronomers.
NASA marks multiple tragedies this week with a special Web telecast commemorating Apollo 1, Challenger and Columbia.
Satellite's mission is to test use of solar sails in space as power alternatives for low-orbit space craft.
Part 1 of a series exploring the cosmos from the perspective of Vatican astronomers.
NASA has officially set a launch date for the STS-135 mission of shuttle Atlantis, the very last space shuttle flight before it's retired.
The replacement of an astronaut puts the spotlight on the physical challenges of working outside in space.
Venus, second planet to the sun, is named for the Roman goddess of beauty and love. While eerily beautiful, the surface of Venus is as hostile as the deepest recesses of space.
The 235-foot rocket carries a spy satellite for a classified mission from the U.S. National Reconnaissance Office.
Atlantis's launch will be NASA's 135th and final shuttle mission into space.
The Stardust-NExT spacecraft will be rapidly snapping pictures of the Tempel 1 comet as they pass at a mere distance of 124 miles.
Activist and author blogs about politics, energy and Earth's resources.
Science journalist blogs about humans and other wildlife.