Researchers observe the first known interstellar comet
Its path suggests it couldn't have been trapped by the Solar System.
Stephen Hawking makes his doctoral thesis available online
He's taking advantage of modern technology to spark an interest in space.
Astronomers just measured a whole lot more than gravitational waves
Researchers around the world are collecting troves of new data from this latest event.
Scientists may have found a Neptune-sized alien moon
It would be the first proof that exoplanets have companions.
Stars can turn into black holes without a supernova
Our assumptions about star death might be misguided.
Construction starts on the world's largest optical telescope
The Extremely Large Telescope has been years in the making.
Live look at the 'alien megastructure' star may solve mysteries
It's a rare chance to look at the star's strange behavior while it's happening.
Most habitable planets may be completely covered in water
Simulations suggest that Earth's ideal mix of land and sea is rare.
Nearby 'super-Earth' may be our best shot yet at finding alien life
LHS 1140b is in just the right orbit for atmospheric studies.