No matter where you observe from, now you can get an astronomical weather forecast.

Incredibly precise measurements of the solar surface show that our star isn't quite as spherical as once thought.

With a Space Shuttle poised and ready in Florida to begin the fifth and final Hubble house call, the venerable orbiting observatory has had a malfunction that will probably delay the repair mission until early next year.

In the 50 years that space physicists have tracked it, the outward "wind" of charged particles coming off the Sun and flowing past Earth has never been weaker than it is right now.

After spending 4½ years doing geologists' bidding on Mars, you'd think that NASA would give its rovers a rest. Instead, one of them has started rolling toward a large crater that it likely won't reach for two years.

After three years of controversy over who discovered it, a large object in the Kuiper Belt has finally been christened by the International Astronomical Union — but the discovery rights are far from settled!

Several lines of physics hint that our universe is just one of many, born in countless separate Big Bangs.

The Pacific Astronomy and Telescope Show drew a large crowds last weekend in Pasadena, California.

Last April a trio of astronomers spotted something dim, warm, and perplexing next to a not-too-distant star in northern Scorpius.

An enormous and famously erratic star in the southern sky might have demonstrated a new kind of stellar explosion during its dazzling eruption in the 1840s.

What was it? While monitoring a cluster of galaxies, the Hubble Space Telescope recorded what seems like a new class of astronomical object brightening and fading over six months.

A gamma-ray burst detected on March 19th was so bright it could be seen with the naked eye. And now astronomers think they know why.

European scientists are excitedly poring over results from the Rosetta spacecraft's close flyby of asteroid Steins, even though an unexpected camera glitch cost them the best views of its cratered surface.

NASA's newest lander has now been scratching, digging, sniffing, baking and tasting samples of Martian polar terrain for more than three months. How long can it survive in the fast-approaching winter — and how much more can it learn?