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 – ...

Stargazers, prepare for the parade of planets that will take place over the next few nights in the sky. Here's what you need to know.

NASA's IMAP mission will delve into the mysteries of the heliosphere, mapping its boundaries and studying solar wind ...