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

Ever since Isaac Newton famously talked about gravity, its dominance as a force in our solar system has been well known. It's ...

When you first learned about the Solar System, you probably saw diagrams that made it look orderly, with planets arranged in ...

An object eight times the mass of Jupiter may have swooped around the sun, coming superclose to Mars' present-day orbit ...

All seven of the other planets in our solar system are about to become visible at once in a great planetary alignment – ...

Images captured by NASA's Solar Dynamics Observatory have revealed that "coronal loops" give off subtle flashes of ...