The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

There are many theories about how dynamics in the early solar system led to the cosmic neighbourhood we now inhabit, but ...

The organic ingredients to life, hints to where Earth’s water came from, and the fundamental building blocks of our planet ...

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.

“Our Solar System’s Kuiper Belt long appeared to ... for objects was complicated by being located in front of the dense background of the galaxy’s center. But now that it’s located in ...

But the auroras on Uranus prove that the lights are beautiful anywhere in the solar system, appearing as thin streaks of bright white light set against the deep azure background of the planet.

There may be an undiscovered planet in the outer solar system whose presence is revealed by the strange orbit of objects beyond the eighth planet Neptune. The tantalizing prospect of a ninth ...