astronomy

The Gaia space probe, launched in 2013, has mapped more than a billion stars in the Milky Way, vastly expanding the inventory of known stars in our galaxy, the European Space Agency said Wednesday.

The search is on for planets that could harbor life, but many of the candidates that we can see are more like gassy Jupiter than rocky Earth. But those planets may be home to rocky moons that can sustain life themselves

The Kepler Space Telescope is on the hunt for potentially habitable planets, but even the most “Earth-like” planets can look dramatically different than our home. One of them, Kepler-438b, is a case study in just how tough finding a second Earth can be.

The last time Comet Lovejoy was visible in the night sky was 8,000 years ago. Now it’s back and visible from the Northern Hemisphere in the coming weeks, and binoculars or a telescope can give you a glowing view of the visitor.

Ahad Momand is the first — and only — Afghan to have gone into space. He was a national hero after his flight in 1988, but it nearly ended in tragedy after a computer malfunction stranded him in orbit without food or water.