SUNSET: 
Why Do We Call Them "Asteroids"?
When astronomers discovered the first objects orbiting between Mars and Jupiter, at first they didn't know what to call them. Today we know them as asteroids, and the creator of that term has finally been identified.
Undue Ado About Asteroid 2013 TV135
The world's news media are making a big deal about a largish near-Earth asteroid discovered on October 8th that has a very slim chance of striking Earth in 2032.
Huge Meteorite Pulled from Russian Lake
Meteorite specialists around the world have wondered whether a massive fragment of the Chelyabinsk mini-asteroid would ever be resurrected from the murky bottom of Lake Chebarkul in Russia. Today they got their answer.
Cloudy with a Chance of Diamonds
Researchers suspect that tiny diamonds could pepper the lower cloud decks of Jupiter and Saturn. These diamonds should be created by lightning strikes and intense atmospheric pressure.
ISON’s Chances for Survival 50/50
Observations and calculations suggest that the comet's nucleus has a 50% chance of surviving its close passage to the Sun, but there are a lot of unknowns that could swing the result either way.
Supervolcanoes on Mars
A new analysis of data from spacecraft orbiting the Red Planet suggests that gigantic calderas lie disguised on the planet’s surface. If the features are volcanoes, they could help explain the mysterious, fine-grain debris that coats Mars.
Uranus's Unlikely Companion
Astronomers have discovered a sizable object sharing the orbit of Uranus. Its existence defies the odds — and within 1,000,000 years it'll slip from the planet's grasp.
To Catch a Comet
A balloon-borne mission launching from the Southwest will aim a telescope at the approaching Comet ISON. While it won't observe the comet at its best, the mission might reveal details about the composition of the icy body and the family it comes from.
Comet ISON to Fly By Mars
On October 1st, Comet ISON will pass closer to Mars than it ever will to Earth. The Red Planet’s rovers and orbiters are ready to send home postcards of the event.
Is Phaethon a "Rock Comet"?
An oddball asteroid discovered 30 years ago apparently gets so hot when near the Sun that rocky minerals on its surface crack, pop, sizzle, and fly off into space.
Methane Goes Missing on Mars
The Curiosity rover conducted super-sensitive tests of the Red Planet's atmosphere for methane — the most abundant hydrocarbon in the solar system — and found none. What does this finding mean for the search for Martian life?
Deep Impact Meets Its End
Primarily known for its up-close comet observations, the Deep Impact spacecraft went on the fritz in mid-August. The mission team scrambled to reestablish communication, but efforts were unsuccessful.
Asteroid Scheme Still Under Way
Despite funding pushback in the House of Representatives, NASA is full steam ahead in plans for its asteroid retrieval mission.
Hisaki: A New Orbiting Planet-Watcher
Japan's latest spacecraft is designed to study gas escaping from the atmospheres of Earth's neighbors in the solar system.
Onward, Voyager 1, to the Stars!
With the release of new results this week, NASA scientists are now confident that their plucky probe, launched 36 years ago, has entered interstellar space.
Glimpse Into Sun Befuddles Theorists
Scientists sneaked a peek into the Sun’s interior, but what they saw contradicts the assumptions made by models predicting solar activity.
An Annular Eclipse on Mars
Not content merely to record the Martian landscape, a camera on NASA's Curiosity rover recently pointed skyward to watch Phobos cross the face of the Sun.
Sun Loses Lithium with Age
Observations of two solar twins — one old and one young — confirm that the Sun has probably destroyed the fragile element as the star has grown older.
WISE Revived for Asteroid Hunt
NASA officials thought they'd switched off the Wide-field Infrared Survey Explorer for good 2½ years ago. But soon it'll be revived for three years to hunt for small asteroids in Earth's vicinity.
Martian Moon Occults Little Brother
NASA's Mars rover Curiosity watched the larger Martian moon, Phobos, pass right in front of the planet's smaller moon, Deimos.
