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

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

The enormous visitor to our solar system may have been about 8 times the mass of Jupiter, and come nearly as close to the sun ...

Mercury is the closest planet to the sun, followed by Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Mercury orbits ...

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

A new study suggests that a close encounter with a massive interstellar object, possibly eight times the mass of Jupiter, may ...

Scientists suggest an interstellar visitor may have altered planetary orbits in our Solar System, reshaping trajectories of ...

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