What do we really know about dark matter?
Some type of mysterious, invisible mass holds the universe together. Here's how scientists are searching for it.
Astronomy: the next generation
Beyond 2020, telescopes will be huge, cost-effective, and easy to service - even the ones in space.
How an amateur changed stellar astrophysics
Thanks to Jay McNeil's discovery, we may soon know what feeds X-ray outbursts from young stars.
Watch as galaxies collide
Even at vast distances, galaxies twist and distort each other into weird shapes. Target these 10 fascinating extragalactic train wrecks.
Face to face with the century's longest eclipse
As the Sun and Moon aligned over Asia, daytime turned to night, and millions witnessed nature's grandest spectacle.
This Month in Astronomy
Bob Berman's Strange Universe
Stephen James O'Meara's Secret Sky
Extreme observing: naked-eye galaxies
The Sky this Month
Glenn Chaple's Observing Basics
David H. Levy's Evening Stars
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