SUNSET: 
Asteroid Flyby Yields New Thinking
When the little asteroid 2011 MD zipped within 8,000 miles of Earth in late June, dynamicists realized they need to change the way they compute such close flybys.
ALCon Meets Under Dark Mountain Skies
With bright stars all night and amateur-astronomical enthusiasm all day, America's biggest coalition of astronomy clubs held a bang-up annual convention.
Two More Moonlets for Jupiter
Astronomers have discovered a pair of tiny satellites traveling far from Jupiter. So which planet — Jupiter or Saturn — now has the most moons?
A Paradigm-Shattering Quasar
A team of European astronomers has discovered the most distant known quasar.But at its heart is a monstrous black hole that could rob theorists of a few nights' sleep.
Tour July's Sky! | June 30th, 2011
Look low in the west at sunset to spy fleet Mercury, toward southwest for Saturn, and in the south for red-hued Antares, the "rival of Mars."
Neutron Star Gobbles Gas, Burps X-rays
Astronomers have observed a neutron star flaring to 10,000 times its original brightness.
Rethinking Galaxies
Edwin Hubble's tuning-fork diagram has helped astronomers classify galaxies for more than 70 years. But recent research shows that it might be time for a makeover — to a "comb" diagram.
A Case for Frozen Hydrogen
Can hydrogen freeze solid in interstellar clouds? If so, it might contribute to a mysterious form of interstellar light absorption.
Is Asteroid 2011 MD Space Junk?
For a while, it seemed possible that the asteroid that will buzz Earth on Monday is actually the upper stage of a rocket.
IceHunters: A Kuiper Belt Search
In the latest citizen science project, you can help NASA hunt new objects in the Kuiper Belt — and perhaps even steer the New Horizons probe toward your lucky find.
Saltwater Ocean on Enceladus
Recent findings hint at the possibility of a saltwater ocean beneath Enceladus's icy surface.
The Star That Changed Our Universe
Modern observers have revisited a dim variable star in the Andromeda Galaxy whose discovery in 1923 rocked the astronomical world.
Asteroid To Buzz Earth Monday, June 27th
Asteroid 2011 MD is expected to pass less than 8,000 miles above Earth's surface around 1 p.m. EDT (17:00 UT) on Monday.
Odd Couple: Phobos and Jupiter
Recently two very different bodies made a joint appearance, as viewed by the stereo camera aboard the European orbiter Mars Express.
Three Great Old Magazines on DVD
The complete collections of The Sky, The Telescope, and Night Sky magazines are now available as DVD-ROMs.
June 15th Lunar Eclipse Observed
Many people in the Eastern Hemisphere enjoyed a long, satisfying, and extraordinarily dark lunar eclipse on June 15, 2011.
Messenger Reveals Mercury Anew
Already a fourth of the way through its basic mission, NASA's well-equipped orbiter has found that the "Iron Planet" is far different than planetary scientists expected.
The Earliest Black Holes
Combining data from the deepest images ever taken in visual/infrared wavelengths and X-rays, astronomers have discovered some of the earliest black holes in the universe.
Black Hole Gobbles Star
A powerful Gamma Ray Burst captured by the Swift space telescope earlier this year gives astronomers a unique chance to study tidal disruption.
A Comet Worth Waiting For?
Observers using the automated Pan-STARRS 1 telescope in Hawaii have found a new comet. As of right now, it might brighten to 1st magnitude in early 2013, but it's far too early to be certain of that.
