SUNSET: 
Observing the Leonids
Here are some tips to help you observe the Leonid meteor shower.
Cosmic Rays from the Kuiper Belt
The "anomalous cosmic rays" have finally had their origin pinned down — in the outer reaches of the solar system.
Dark Matter Gets a Reality Check
There's no way to avoid it; galaxies really are surrounded by halos of unknown, invisible stuff.
A Double Star's Planet
Astronomers have discovered the first planet that orbits one star of a close pair.
Gamma-Ray Burst Caught in the Act
A fast worldwide alert enables astronomers to snag their best-observed gamma-ray burst ever.
Midsize Black Holes in Midsize Star Clusters
Black holes with several thousand times the Sun's mass have unexpectedly turned up in the cores of globular clusters.
SETI@home Spells Out New Plans
Your computer may soon be able to join a widened search for ETs. Above: The Parkes radio telescope in Australia.
An Average Perseid Meteor Shower
This year's Perseids performed just about as expected, though hazy, humid skies hindered the view from many places.
Not a Quark Star After All?
A weird object announced last April appears to be an ordinary neutron star, not a strange new type of matter.
A Familiar Orbit in a New Crop of Exoplanets
A well-behaved giant planet orbits the Sunlike star 55 Cancri at the same distance Jupiter orbits the Sun.
Hubble's Infrared Camera Back in Business
Dead for three years, the Hubble Space Telescope's NICMOS camera is again providing infrared views of the universe.
Big Bang Picture Sharpens Up
New, sharper maps of the cosmic microwave background radiation are telling astronomers they're on the right track.
A Cyclic Universe?
Maybe the Big Bang wasn't the beginning, but only the latest in an endless cycle of destructions and rebirths.
Mars Odyssey Pays Early Dividends
After successfully settling into orbit around the Red Planet, NASA's Mars Odyssey has begin its 2½-year mapping mission.
A Galaxy Turning Backward?
A spiral galaxy's arms trail behind when it rotates, right? Not always.
Giant Eye Views the Horsehead
The cosmic chess piece, the Horsehead Nebula, is seen in all its glory through the eyes of the VLT.
Close-Up of an Alien World
The lunar surface consists of more than just craters and mare. Here's a guide to some of the other lunar features.
