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 ...

Illustration comparing the planets of the Solar System and the Sun on the same scale. The planets are shown to scale relative to each other but their distances are not. From left to right the bodies ...

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 ...

Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky A cloud of collapsing gas created our Sun, the first thing to form in ...

There’s a bit of a paradox about our galaxy: it’s both jam-packed with stars and cavernously empty. The Milky Way is crowded in the sense that it holds hundreds of billions of stars, as well as ...

The formation of our solar system from a singular nebula raises an intriguing question: why did each planet develop with a ...

There's something big missing from our solar system — and that may be a good thing. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Planetary ...

This article was originally featured on The Conversation. Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky A cloud of ...