Here's why the surface of Mercury is so dark
The tiny planet is covered in a light-absorbing element.
The Hubble has seen farther back in time than ever before
The space telescope spotted a star from just 400 million years after the Big Bang.
NASA's next space telescope sees 100 times more than Hubble
WFIRST's extremely large viewing area will help you understand the universe.
Astronomers may have found the Solar System's 9th planet
No, it still isn't Pluto.
NASA's closest-ever Ceres photos reveal more odd shapes
The dwarf planet is pretty, but still mysterious.
See what every star system Kepler's found looks like compared to ours
See all 1,700 exoplanets we currently know about
That star's 'alien megastructure' is likely just a swarm of comets
It's tempting to think that an unusual star is enveloped by alien satellites, but the truth is likely far more pedestrian.
Astronomers find pure oxygen leaking from Rosetta's comet
This discovery could revolutionize our understanding of how the solar system came to be.
Astronomers find the first planet known to orbit a white dwarf
Astronomers have spotted a planet slowly being eradicated by a dying star.