Add Yahoo as a preferred source to see more of our stories on Google. An illustration showing Planet Nine, a hypothetical, undiscovered planet in our solar system. New research now suggests the ...

Add Yahoo as a preferred source to see more of our stories on Google. Jupiter is already the biggest planet by far in our solar system, but new research suggests it was somehow once even larger than ...

The newly discovered moons are "irregular" satellites, meaning they are small (averaging about 3 km across) and have distant, often eccentric orbits.

Scientists may have discovered a dwarf planet far beyond Neptune — an unearthing that may disprove a longstanding theory about the possibility of a giant ninth planet. The dwarf planet's existence ...

An artist's impression of a planetary system with four planets, around a small red star, called LHS1903 with a large reddish-brown rocky planet with craters is visible in the foreground and three ...

WASHINGTON, March 13 (Reuters) - Astronomers have identified a quartet of small rocky planets orbiting Barnard's star - one of our closest stellar neighbors - though they concluded that all of them ...

LONDON — The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper's authors have ...