SUNSET: 
Plumes on Europa
New Hubble Space Telescope observations provide the best evidence yet that Jupiter's icy moon spits out water vapor from its surface. If real, such plumes could reach more than 100 miles above the little world's surface and rain down an extraterrestrial form of snow.
Comet ISON: What We've Learned
Comet ISON's untimely demise didn’t prevent scientists from studying it, revealing the comet to be smaller than previously thought and harboring high concentrations of carbon.
New View of Saturn's Hexagon
NASA's Cassini spacecraft has captured phenomenal images of the gigantic weather system at Saturn's north pole. This so-called "hexagon" is nearly three times wider than Earth is.
China Launches Lunar Mission
If all goes well, on December 14th the Moon will host its first soft-landing spacecraft since 1976.
So It Ends for Comet ISON
After more than a year of anticipation, there is no dazzle, only a dud.
Comet ISON Becomes a Nail-Biter
Is the comet dying, just three days before its closest pass by the Sun? There are signs that its nucleus has stopped producing anything.
Comet ISON Diving Sunward as its Moment of Truth Nears
Tiny, greenish white, and harder to see every day, Comet ISON is descending toward the sunrise horizon and its November 28th perihelion.
MAVEN Heads to Mars
NASA's next orbiter has successfully launched and is en route to the Red Planet. When it arrives, it will pry into the secrets of Mars's climate, both past and present, and hopefully reveal how the cold, dry world lost most of its ancient atmosphere.
The Next New Meteor Shower
Astronomers confirm that debris from Comet 209P/LINEAR should create a sky show on May 24, 2014 — but it looks less likely that a “storm” is in the works.
"Tails" of a Very Unusual Asteroid
What at first looked to be a comet that had snuck its way into the asteroid belt now appears to be a bizarre, fast-spinning space rock that's occasionally shedding tails of dust.
New Chelyabinsk Results Yield Surprises
The mega-meteor that exploded over Russia last February has provided impact specialists with some surprising — and sobering — revelations.
Indian Mars Mission Launches
India's first mission to the Red Planet launched successfully November 5th from a barrier island off the country's coastline. The mission will study Mars's atmosphere and surface and is an important milestone for the country's space agency.
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.
