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 ...

There are 8 planets in our solar system. The planets orbit the Sun in elliptical trajectories, and they are all different in size, composition, temperature, and characteristics. The planets can be ...

Our Solar System has eight planets, a few dwarf planets and more than 200 moons. But wait. Are you seeing double? Or did ...