So in some sense, alien worlds were not first discovered in the 1990s or even the 1980s. It took nearly a century to fully ...

For the better part of a century, we believed there were nine planets in our solar system, with Pluto being the farthest from the sun. Since the discovery of more Pluto-sized dwarf planets, that ...

Life could have the time and energy to arise and prosper on Earth-like worlds in the rapidly shrinking "Goldilocks zones" ...

Decades of constant X-ray emission from the Helix Nebula’s white dwarf suggest debris from a Jupiter-sized planet steadily rains upon the star.

This is particularly puzzling, as a vast majority of meteorites can be traced to some well-known parent body—whether that be ...

A surprising chemical difference between Pluto and Sedna, another dwarf planet in the distant Kuiper Belt, is helping ...

The latest data suggests there may be "a subtle, regular change in the X-ray signal every 2.9 hours, providing evidence for the remains of a planet exceptionally close to the white dwarf," the CXC ...

Astronomers have confirmed the existence of four planets orbiting a star less than 6 light-years away with help from some of ...