Explore astronomy, from the latest trip to the International Space Station to alien planets outside our solar system.
Real-life 'X-Files' reveal policy of destroying documents related to UFO investigations because they would have taken up too much filing space.
Learn more about the blue-green planet that is four times as large as Earth and is covered by methane gas clouds.
Video: Cosmonaut Yuri Gagarin's first orbital flight made history in 1961 and set the pace for the U.S.-Soviet space race.
Video: Photographer Terje Sorgjerd speaks about the week he spent capturing amazing pictures and video of the Northern Lights.
Long before the first lunar landing, dogs, chimps and monkeys flew beyond our atmosphere to test the influence of space on living organisms.
What on Earth? These photos give a small glimpse of the captivating beauty of our planet.
Black holes are some of the most mysterious objects in the universe — what is left behind after a star has collapsed. NASA has compiled several dramatic images of what are believed to be black holes 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.
New telescope called SOFIA, which is actually a modified 747 jet, releases photographs from its first science mission.
New journal looks at sex on Mars and questions why NASA is so silent on the subject.
Scientists have dubbed the mysterious mass of unseen dark matter 'Galaxy X.'
The beautiful blue orb of Neptune is the eighth and farthest planet in our solar system from the sun. Thanks to Voyager 2 and the Hubble telescope, we can see Neptune as never before.
NASA's WISE infrared telescope reached its one-year anniversary in December. To celebrate, here are four new dazzling images of the scope's most recent observations.
Video: Missed the total lunar eclipse last night? With the help of a little video magic, watch it happen much faster.
Video: For the last 24 hours, speculation that NASA might announce that ET has finally phoned home went viral.
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