SUNSET: 
Kepler's Outrageous Six-planet System
NASA's Kepler space telescope has found1,200 likely new planets, including the most bizarre planetary system yet.
The Crab Nebula Flickers!
A recent study shows that the Crab Nebula, long considered a steady source of X-rays, actually fluctuates.
Thunderstorms That Shoot Antimatter
The Fermi satellite was launched to observe gamma rays coming from the distant universe. It has also found positrons coming from below.
Kepler's Dense, Rock-and-Iron Planet
With just 1.4 times Earth's diameter but 4.6 times Earth's mass, Kepler-10b has the average density of iron.
Spirit's Quiet Anniversary
The first of NASA's twin rovers reached the Martian surface on January 3, 2004, but it hasn't been heard from in nearly a year.
SOHO: World's Greatest Comet Finder
The Solar and Heliospheric Observatory, a spacecraft that's spent 15 years staring at the Sun, recently recorded its 2,000th comet.
Japan's Akatsuki Goes AWOL
A spacecraft that was supposed to slip into orbit around Venus for a two-year study of its atmosphere has instead flown right by — and won't be back for another 7 years.
Troubles Surface for Webb Telescope
Astronomers expect the James Webb Space Telescope to show them amazing things, such as the first galaxies forming. But getting this revolutionary spacecraft to the launch pad is going to cost a lot more and take a year longer than expected.
Comet Hartley 2: Full of Surprises
During a brief flyby just two weeks ago, NASA's Deep Impact spacecraft revealed never-before-seen details about dynamic Comet Hartley 2 that have left mission scientists elated — and confused.
Hayabusa Brings Home Asteroid Dust
It's a fairy-tale ending to an against-all-odds story: Japanese scientists have identified bits of asteroid dust inside the sample canister of a spacecraft that, somehow, made it back to Earth seven years after launch.
Why is the Milky Way Blowing Bubbles?
Using gamma-ray eyes on NASA's Fermi spacecraft, astronomers now see that our home galaxy sports a matched pair of enormous and recently formed bubbles. It's a mystery how and why they formed.
Mr. Hartley's Amazing Comet
For the fifth time, a spacecraft has revealed close-up images of a comet's nucleus. Comet Hartley 2 is perhaps the wildest and most dramatic of them all.
Titan's Hazes: A Rich Brew
With a little help from neighboring Enceladus, Saturn's big moon Titan might well be cooking up an incredible mix of prebiotic molecules in its upper atmosphere.
Sun's Heliopause: A Moving Target
A NASA spacecraft has found the collision of the Sun's magnetic bubble with interstellar space is more varied and dynamic than anyone had imagined.
Phobos: A Chip Off of Mars?
New results from the European spacecraft Mars Express suggest that the Martian moon Phobos has a lot in common with the planet it orbits.
The Moon Through LRO's Eyes
For the past year, the seven instruments on NASA's Lunar Reconnaissance Orbiter have mapped the Moon up, down, and sideways — and planetary scientists are reaping the results.
A Ghostly Cosmic Pinwheel
Somewhere in Pegasus, a swollen, aging star has begun its death spiral figuratively and literally — throwing off matter that's taken the shape of a delicate yet perfect spiral.
The Incredible Shrinking Moon
Planetary scientists have long considered the Moon dead, geologically speaking. But new high-resolution views of the lunar surface argue otherwise.
Astro2010: U.S. Astronomy's Crystal Ball
If you had $12 billion to spend on ground- and space-based observatories over the next 10 years, how would decide what to build? A 255-page National Research Council study, just released, provides some answers.
A Lunar Debate: Dry or Wet?
It's been 40 years since Apollo astronauts returned with dusty chunks of the Moon — samples that offer conflicting views of lunar history.
