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 ...

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

A spacecraft operated by the European Space Agency and the Japan Aerospace Exploration Agency has made its final flyby of Mercury, as scientists now work to guide ... the invisible about the solar ...

However, this year a powerful new telescope is coming online that could prove once and for all that there really is a ninth planet in our Solar System ... entertainment. Download now for all ...

The solar system may hold ... their work builds on Sheppard and Trujillo’s findings. Brown, known for his role in Pluto’s reclassification, described Planet Nine as a potential breakthrough.