20 October 2014, 02:43 AM ET
Comet Siding Spring came within just 87,000 miles of the Martian surface at 2:27 p.m. EDT today — about one-third of the distance between Earth and the moon. The comet barreled by at 126,000 mph relative to the Red Planet, NASA officials said.
18 October 2014, 09:18 PM ET
NASA scientist Dr. Michelle L Thaller tells Space.com's @MiriKramer what you need to know about comet Siding Spring's fly-by, its implications for the Red Planet and how humans will be able to observe it. Full Coverage: http://goo.gl/0cnCEb
17 October 2014, 05:05 PM ET
The top-secret nature of the X-37B missions has sparked a number of conspiracy theories. Here are some ideas about the X-37B's purpose.
17 October 2014, 11:06 AM ET
Comet Siding Spring will zoom within 87,000 miles of Mars at 2:27 p.m. EDT on Sunday (Oct. 19). Scientists will observe the flyby using the fleet of spacecraft already at Mars, studying the comet and any effects its dust has on the planet's atmosphere.
16 October 2014, 07:38 PM ET
A comet is on course for a super-close approach with the planet Mars this Sunday (Oct. 19) in a rare celestial encounter. If you have a moderate-size telescope, you might be able to spot the icy wanderer as it nears the Red Planet, weather permitting.
16 October 2014, 04:35 PM ET
Millions of people across North America will have a chance to observe a partial solar eclipse next week, weather permitting.
15 October 2014, 08:34 AM ET
A mysterious stone slab from the 12th century B.C. is a combination sundial and moondial, a new study finds. The slab would've helped ancient skywatchers track the movements of the sun and moon during heavenly events.
14 October 2014, 10:28 AM ET
Scientists previously thought that the moon's volcanic activity died down a billion years ago. But new data from NASA's Lunar Reconnaissance Orbiter, or LRO, hints that lunar lava flowed much more recently, perhaps less than 100 million years ago.
09 October 2014, 07:21 AM ET
The discovery of extraterrestrial beings — be they slimy microbes or little green men — would dramatically change the way we humans view our place in the universe. But would it shatter religion? Well, that depends on what you believe.
09 October 2014, 07:12 AM ET
Frigid lakes bombarded by UV radiation and boiling, acidic springs are some of the otherworldly Earth environments where scientists plan to hunt for clues to life on Mars.
08 October 2014, 11:25 AM ET
The moon turned an eerie blood-red hue during a total lunar eclipse early Wednesday (Oct. 8) in an epic skywatching treat for amateur astronomers. See the amazing photos and their impressions of the lunar event.
08 October 2014, 09:31 AM ET
The full moon darkens and grows reddish during a total lunar eclipse early today that dazzles observers around the world.
07 October 2014, 05:59 PM ET
Weather prospects for Wednesday's total lunar eclipse are great for observers hoping to catch a glimpse of the 'blood moon' from around the United States.
07 October 2014, 09:55 AM ET
Want to study high-energy particles streaming through the cosmos at nearly the speed of light? There's an app for that.
06 October 2014, 07:29 PM ET
The Milky Way may be home to some 3,000 extraterrestrial civilizations but the vast distances between our galactic cousins will make contact extremely rare, a new study concludes.
06 October 2014, 01:35 PM ET
Observers of Wednesday morning's total lunar eclipse might be able to catch sight of an extremely rare cosmic sight.
30 September 2014, 12:42 PM ET
NASA's Cassini spacecraft has spotted an odd islandlike feature in Ligeia Mare, one of Titan's largest hydrocarbon seas. Scientists don't know what to make of the structure, which covers about 100 square miles.
30 September 2014, 11:15 AM ET
Pictures from space show that fall is in full swing in parts of North America. Clusters of trees have shed their summer greens in favor of autumnal oranges and reds around the Great Lakes and New England.
27 September 2014, 10:22 AM ET
A plasma bubble likely contributed to the helicopter radio communication failure during the battle of Takur Ghar, part of Operation Anaconda during the war in Afghanistan.
26 September 2014, 07:41 PM ET
The White House is looking to data from NASA's space shuttle program to help in the fight against climate change. NASA will publicly release hi-res topographic maps of the globe to help other nations prepare for a changing environment.
26 September 2014, 01:50 PM ET
The finding suggests that water is commonly incorporated into newly forming planets throughout the Milky Way galaxy and beyond, researchers said — good news for anyone hoping that Earth isn't the only world to host life.
25 September 2014, 11:45 AM ET
Researchers using data gathered by NASA's Hubble Space Telescope have determined that the supernova SN 1993J — which was first observed in 1993, as its name suggests — occurred because one star nabbed hydrogen from another.
25 September 2014, 08:40 AM ET
It maybe the 'answer to ending the political gridlock in America' said the former U.S. president while speaking to ISS crew members Reid Weisman and Alexander Gerst about how they work in unison with international partners.
24 September 2014, 10:48 PM ET
A Neptune-sized planet beyond the solar system has telltale traces of water vapor in its atmosphere, making it the smallest known wet exoplanet yet, scientists say. The exoplanet HAT P-11b is about four times the size of Earth and about 124 light-years aw
24 September 2014, 02:33 PM ET
Observations of planet HAT-P-11b by the Hubble, Spitzer and Kepler Space Telescopes were used to make the discovery. The planet is 120 light-years away in the constellation of Cygnus.
Full Story: http://goo.gl/8h7zEP
23 September 2014, 05:55 PM ET
Supposed evidence of gravitational waves from the dawn of time may actually be the signature of dust and gas in our own Milky Way galaxy, a new study reports.
22 September 2014, 10:38 AM ET
After a 10-month journey through deep space, NASA's MAVEN probe arrived in Mars orbit late Sunday, on a mission to help determine why the Red Planet changed from a warm and wet place in the ancient past to the cold, arid world it is today.
19 September 2014, 02:04 PM ET
The AMS particle detector aboard the International Space Station has found more evidence of dark matter in cosmic ray data.
19 September 2014, 11:22 AM ET
Dragon will lift off atop SpaceX's Falcon 9 v1.1 rocket at 2:16 a.m. EDT Saturday from Florida. Dragon will fly nearly parallel to the U.S. East Coast, so the launch should be visible in varying degrees along much of the Eastern Seaboard.
17 September 2014, 02:00 AM ET
Astronomical clues could pinpoint the day Claude Monet painted "Impression, Soleil Levant (Impression, Sunrise)," the piece that lent its name to the Impressionist art movement.
16 September 2014, 02:25 PM ET
In the 1998 movie 'Armageddon,' an asteroid the size of Texas threatens to collide with Earth in 18 days. Despite its entertainment value, the film is fantastically inaccurate, astronomer Phil Plait said.
15 September 2014, 05:45 PM ET
A new project aims to send a special message from Earth — a type of global "selfie" — into space, by uploading it to a spacecraft traveling through the cosmos on its way to Pluto.