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

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 ...

At the farthest edges of the solar system, strange objects follow paths that defy easy explanation. This story investigates ...

A rocky exoplanet in the LHS 1903 system defies planet formation models, hinting that gravitational upheaval reshaped the red dwarf’s four worlds.

Astronomers have spotted an unusual 'inside-out' planetary system where a rocky world seems to have formed far beyond the realm typically reserved for gas giants.

By Will Dunham WASHINGTON, Feb 14 (Reuters) - Astronomers have observed a planetary system that challenges current planet ...

A newly studied solar system breaks the usual planet pattern, raising fresh questions about how rocky and gas planets form.

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, ...

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 ...

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 ...