Two massive planets may have once existed in early solar system before being ejected, leaving behind evidence in unusual ...

Add Yahoo as a preferred source to see more of our stories on Google. (Ianm35/iStock/Getty Images Plus) The Solar System is one of the comforting constants of human existence. No matter what else we ...

A rare meteorite has revealed evidence of a massive lost world that once orbited the young Sun before being destroyed in a catastrophic collision. The discovery suggests some early planets formed from ...

A Jupiter-size exoplanet orbiting a dead star baffled astronomers. But the planet named WD 1856 b could preview the fate of ...

Is there a massive undiscovered planet on the outer reaches of the solar system? The idea has been around since before the discovery of Pluto in the 1930s. Labeled as planet X, prominent astronomers ...

Our solar system has two ice giants, Uranus and Neptune, but there may have been a third. According to a new study published in the journal Icarus, this extra world might have triggered a violent ...

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 ...

All of our solar system’s planets are lining up to parade through the night sky at once. This extraordinary celestial event will see the sky scattered with seven visible planets in what is known as a ...

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 ...

Interstellar comet 3I/ATLAS, the third object ever confirmed to have originated beyond our solar system, is heading back into ...

(Ianm35/iStock/Getty Images Plus) The Solar System is one of the comforting constants of human existence. No matter what else ...