Discover all you need to know about the planets, comets and asteroids that orbit the Sun and make up our Solar System. Read the varying theories about the origins of the Solar System and find out how you can become an amateur astronomer and view it with your own eyes.

The planet Mercury is the smallest and nearest planet to the Sun in the Solar System.

The planet Neptune is the furthest planet from the Sun and is orbited by Triton.

Satellites orbit planets, which orbit the Sun, which in turn orbits the centre of the Milky Way. But why?

How did the planets, moons and asteroids in the Solar System form? There is a surprising amount of debate and several strong and competing theories.

19th-century astronomers went beyond cataloguing the skies to understanding their composition and predicting what could not be seen.

Tour the Solar System with our essential facts and figures.

The challenges of measuring everything from a fast-moving, wobbly platform through a haze.

What Pluto, Ceres, Haumea, Makemake and Eris, the dwarf planets lack in size they make up for in mystery. 

Handy tables of orbits, mass, rotation periods and tilts for the planets and their moons in the Solar System.

The planet Saturn: truly massive and stunningly beautiful with its rings. It’s also home to amazing moons like Titan.

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