A hundred years ago today, Einstein’s theory of gravity was first put to the test when Arthur Eddington observed light “bending” around the sun during a solar eclipse. A century later, scientists are still searching for the limits of the theory.

Researchers estimate that if the massive ice deposits melted, they'd cover the planet in 5 feet (1.5 meters) of water.

A study of dust in the disk around the star HD 163296 suggests we're glimpsing a gravitational interaction between giant planets and much-smaller objects, the future asteroids and comets of this newly forming solar system.

Watch 2 Russian cosmonauts perform a spacewalk outside the International Space Station (ISS) on Wednesday, May 29.

Citizen scientists: NASA’s OSIRIS-REx mission needs your help choosing its sample collection site on asteroid Bennu ... and your extra eyes to look for whatever else might be interesting.

A new survey algorithm - called Transit Least-Squares - has just caused the number of known, rocky, Earth-sized worlds orbiting distant stars to grow again, as astronomers add another 18 exoplanets to the list.

It wasn't visible to the eye, but some telescope users in Earth's Southern Hemisphere caught it at its May 25 closest approach. Now Northern Hemisphere observers will get their chance. Charts here, and check out this cool video!

It's amazing we can detect comets in distant solar systems at all! These are the first 3 exocomets found in data gathered by TESS, NASA's newest planet-hunter. The comets orbit the famous star Beta Pictoris.

What happens when young stars brush past each other? A lot, according to a new study suggesting our solar system contains comets stolen from another star 4.5 billion years ago.

"Here is the video I shot, be prepared to be mind-blown!" Marco Langbroek wrote on his website SatTrackCam Leiden (b)log, where he shared an amazing capture of dozens of SpaceX Starlink internet satellites chugging along, in a straight line, across the heavens.