Mercury is the innermost and smallest of the eight major planets in our Solar System, orbiting closest to the Sun. Though ...

PASADENA, Calif.–The International Astronomical Union (IAU) today downgraded the status of Pluto to that of a “dwarf planet,” a designation that will also be applied to the spherical body discovered ...

Our Solar System has eight planets, a few dwarf planets and more than 200 moons. But wait. Are you seeing double? Or did every planet suddenly get a twin? Where would each planet’s double fit in? Why ...

James is a published author with multiple pop-history and science books to his name. He specializes in history, space, strange science, and anything out of the ordinary.View full profile James is a ...

This artist’s concept depicts one of the solar system’s inner planets slamming into Earth after being nudged on a collision course by a passing star. Such a world-shattering cataclysm is extremely ...

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 ...

The Sun is orbited by eight planets, at least five dwarf planets, tens of thousands of asteroids, and around three trillion comets and icy bodies. Although not all objects of the solar system are as ...

When I was a kid, there were nine planets. Now we know of thousands! But that includes exoplanets, alien worlds that orbit alien suns. Only eight planets call our solar system home. Or there might ...

One of the solar system’s most fortuitous conga lines occurred in the late 1970s, when the four gas giants—Jupiter, Saturn, Uranus, and Neptune—formed a neat cosmic column, allowing the Voyager ...

The Solar System is more than just planets; it is home to a dazzling variety of moons, each with its own unique charm. Some are icy and serene, others are stormy or volcanic. Among the many satellites ...