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

Watch this video to find out more about the Earth, planets in our Solar System and other planets far ... The largest object is the asteroid belt is the dwarf planet Ceres, which is 950km in ...

The Solar System doesn't get much colder than the Kuiper Belt. Out past the orbit of Pluto, far from the warmth of the Sun, drifts a vast expanse of icy rocks and dwarf planets thought too cold to ...

Astronomers think that a dwarf planet hiding in the middle of our solar system could be a source of frozen water. The dwarf ...

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

The two are known as our solar system's 'ice giants'. Our solar system's largest planets, the gas giants, are so large that some of their component parts would dwarf Earth. The bodies in our solar ...

Planets with suns like Wolf 359 are subject to huge blasts of radiation that raise questions about their long-term ...

That’s because Pluto was downgraded from a “planet” to a “dwarf planet” in 2016 by ... that there really is a ninth planet in our Solar System. The same year that Pluto was ignominiously ...

Opinions expressed by Forbes Contributors are their own. Jamie Carter is an award-winning reporter who covers the night sky. Computer simulations suggest that there is an undiscovered Earth-like ...

This mysterious ninth planet could be found within the next ‘two years’, one expert said (Picture: Getty Images/iStockphoto) We’re closer than ever before to knowing whether there is a ninth ...