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. Digital art of distant planet - Dottedhippo/Getty Images On August 24, 2006, our solar system lost a planet. It wasn't by ...

Their observations of a faint, cool M-dwarf star called LHS 1903 revealed a system with a rocky world at its outer edge. LHS ...

LHS 1903 flips rock and gas on their heads, hinting that late-born planets can rewrite the rules around common red dwarfs for now.

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 ...

The Sun is an incandescent but benevolent dictator. For billions of years, it’s kept our star system well organized through the influence of its powerful gravity. All the planets revolve around it on ...

The shape of a planet's orbit is one of its fundamental properties, along with its size and distance from its host star. Earth has a nearly circular orbit, but some planets outside our solar system, ...

Astronomers have observed a planetary system that challenges current planet formation theories, with a rocky planet that formed beyond the orbits of its gaseous neighbors, possibly after much of the ...

An object eight times the mass of Jupiter may have swooped around the sun, coming superclose to Mars' present-day orbit before shoving four of the solar system's planets onto a different course. When ...

Studying the orbits of thousands of exoplanets shows that large planets tend to have elliptical orbits, while smaller planets tend to have more circular orbits. This split coincides with several other ...

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 ...