SUNSET: 
A Deep (Impact) Mystery
Deep Impact's in-your-face encounter with Comet Tempel 1 on July 4, 2005, created an enormous splash of dust and gas far more massive than anyone predicted. Some 3½ years later, planetary scientists are still struggling to understand what happened.
The New Face of Mercury
NASA's Messenger spacecraft slipped past the innermost planet on October 6th, revealing an amazing Mercurian landscape never before seen at close range.
Hubble Shuts Down, Repairs Delayed
With a Space Shuttle poised and ready in Florida to begin the fifth and final Hubble house call, the venerable orbiting observatory has had a malfunction that will probably delay the repair mission until early next year.
Opportunity's Mad Dash
After spending 4½ years doing geologists' bidding on Mars, you'd think that NASA would give its rovers a rest. Instead, one of them has started rolling toward a large crater that it likely won't reach for two years.
Rosetta's "Jewel in the Sky"
European scientists are excitedly poring over results from the Rosetta spacecraft's close flyby of asteroid Steins, even though an unexpected camera glitch cost them the best views of its cratered surface.
Phoenix Surpasses 90-day Milestone
NASA's newest lander has now been scratching, digging, sniffing, baking and tasting samples of Martian polar terrain for more than three months. How long can it survive in the fast-approaching winter — and how much more can it learn?
NASA Space Observatory Gets New Name
The best-ever gamma-ray satellite is living up to expectations and NASA has just given it a new name.
New Enceladus Closeups Now Arriving
The Cassini spacecraft is returning the data from Monday's close flyby of icy Enceladus, and NASA is putting up the first raw images.
Titan Makes a Splash
It's not covered by a global ocean, as theorists once thought. But Saturn's big moon does sport pools of liquid ethane big enough to float anyone's boat.
NASA Turns 50: Take a Photo!
The U.S. space agency was founded 50 years ago today. You can celebrate by finding your favorite NASA photograph.
An Electrifying Whodunit
Thanks to a quintet of identical spacecraft, space physicists have settled a decades-old debate over what triggers violent electromagnetic substorms inside Earth's magnetosphere.
Earth and Moon Dance for a Far Camera
From more than 30 million miles away, a NASA spacecraft snapped away as the Moon made a graceful pass in front of Earth's colorful disk.
Mars's Ancient Water Works
New observations from a NASA orbiter reveal that water and rock freely mingled across (or under) much of the Red Planet's surface.
Mercury: The Incredible Shrinking Planet
During its first flyby of Mercury, NASA"s Messenger spacecraft found much less iron on the planet’s surface than expected and a cloud of ionized atoms — including water — caught up in the planet’s magnetosphere. And that’s just for starters.
SOHO Tallies Its 1500th Comet
The Solar and Heliospheric Observatory has now found more comets than all other comet discoverers put together — not bad for a spacecraft that was designed to study the Sun.
Ulysses' Space Odyssey Ends on July 1st
The only space mission ever to study the Sun’s poles directly will turn off at month’s end after a long life of trial and triumph.
GLAST Heads Up, Up, and Away!
NASA's newest space observatory is safely in orbit and getting ready to probe the high-energy universe.
Moonlets Perturb Saturn’s Ring
New observations from Cassini show small satellites are responsible for Saturn's F ring looking a little frazzled.
NASA UV Satellite Powers Down
After five years in orbit, CHIPSat enters a hibernation that may — or may not — be permanent.
"Holy Cow!" — Phoenix Spots Ice
If the Phoenix lander hadn't been able to find ice on Mars within reach of its robotic arm, NASA scientists would have been majorly bummed. They needn't have worried.
