SUNSET: 
Streaking Snowballs in Saturn's F Ring
Self-destructing clumps of ice particles are changing the face of Saturn's bizarre F ring. No longer unseen ghosts, these theoretically predicted objects are putting on quite a show for NASA's Cassini spacecraft.
Asteroid Mining for Fun and Profit
A cadre of space entrepreneurs has hatched a plan to identify thousands of small near-Earth asteroids — and then to exploit the mineral wealth that many of these space rocks are certain to contain.
WISE Identifies Mystery Sources
Astronomers are using infrared observations from NASA's WISE spacecraft to identify sources seen at energies a million times greater. The work may help astronomers figure out whether they've detected unknown cosmic phenomena.
Sky & Telescope's New Moon Globe
The year-long effort was time consuming and tedious, but S&T's staff is proud to unveil the first wholly new globe of the lunar surface in more than four decades.
Kepler Mission Gets Four More Years
NASA's incredibly successful planet-hunter has had its mission extended to 2016 — giving it extra time to find Earthlike worlds in Earthlike orbits.
Vesta: A Study in Black and White
NASA's Dawn spacecraft is scrutinizing the second-largest asteroid from close range. Yet some aspects of Vesta's surface — especially splashes of very bright and very dark material — are puzzling.
Hubble's Hidden Treasures Competition
Try your hand at creating a beautiful Hubble image and you might win an Apple iPod Touch or iPad.
March Madness on Mercury
After a full year of scrutiny by NASA's Messenger orbiter, the innermost planet is revealing itself to be unique — and downright confounding — to the project's scientists.
How Big is the Sun, Really?
By carefully recording the track of Mercury when it crossed the solar disk in 2003 and 2006, observers have measured the Sun's diameter more accurately than ever before.
Mars and Moon: Not Dead Yet?
The Martian and lunar surfaces were thought to be geologically dead. But twitches of recent activity are turning up in extreme closeups from orbiting spacecraft.
New Evidence for Ancient Martian Ocean
For decades planetary scientists have speculated about whether a huge depression that dominates the northern hemisphere of Mars was once flooded with water eons ago. Now radar soundings are showing that the answer might be "yes".
Show Your Support for Pluto's Probe
NASA's New Horizons spacecraft is now just 3½ years from its historic flyby of Pluto. Mission scientists have launched a petition to have the spacecraft commemorated on a U.S. postage stamp — and they want you to sign it!
Opportunity Takes a Bow, Gets Some Rest
It's been eight years since NASA dropped twin rovers onto the Martian surface. Spirit succumbed to the planet's harsh conditions in 2010, but Opportunity continues to amaze mission scientists with its longevity and scientific productivity.
Farewell to Rossi's Explorer
Last week, NASA engineers reluctantly shut down the Rossi X-ray Timing Explorer, a largely unheralded orbiting outpost that relayed a steady stream of observations for 16 years.
GRAIL's Twins Safely Reach the Moon
Braking rockets fired on cue yesterday and today, placing twin spacecraft in lunar orbit. In the coming months, they will exploit the Moon's own gravity to revolutionize what we know about the lunar interior.
A Breathtaking View of Titan
Here's a "holiday treat" featuring Saturn's largest moon and some dramatic lighting geometry, courtesy of NASA's Cassini orbiter and its imaging team.
Kepler Finds Two "Deep-Fried" Planets
The incredibly successful Kepler spacecraft is discovering alien solar systems at a dizzying pace. Now it's found a system in which two planets have apparently survived a journey inside their host star, during its swollen red-giant phase.
NASA Taps a Rocket Scientist
With probes on the way to the Moon, Mars, and Pluto — and a multibillion-dollar space telescope gobbling up shrinking funds — astronomer and former astronaut John Grunsfeld agrees to take the helm of the space agency's science division.
Asteroids, Planets, and Moons, Oh My
This week’s meeting of the American Geophysical Union brought together a variety of interesting science results, from water on Mars to the Sun’s effect on the Moon’s surface. Here’s a selection of curiosities for your perusing pleasure.
Kepler Finds a Possibly Habitable World
The hits just keep on coming for NASA's Kepler spacecraft. Today mission scientists announced that they've identified a thousand more candidate planets around other stars. One is Kepler-22 b, a world somewhat larger than Earth where you likely could walk around in shirtsleeve temperatures.
