Read all about the eight different planets in the Solar System - Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune - and how they differ. Plus, find out why Pluto was reclassified as a dwarf planet in 2006, and discover fascinating facts about tidal forces.


The planet Uranus: first of the planets to be found in the modern era and dressed in rings. It orbits the sun on its side and the wrong way round!


The planet Venus: known for love, rotational contrariness, crushing atmospheres, furnace-like temperatures and acid rain.

James Bradley.jpg

As we prepare for the Transit of Mercury here at the Royal Observatory our curator, Louise Devoy, looks back to observations made here in 1753.


How high can you go? Get the low-down on all that's 'high up' in our fact-packed infographic. Who has flown the highest? Could we really build an elevator to space?


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

Above and Beyond infographic - How far? (tile)

How far can you go? Get all the far-out facts in our infographic. What's the furthest man-made object in space, and what's the longest non-stop flight of a bird?

Hunting Moon © Jean Baptise Feldmann, Astronomy Photographer of the Year People and Space Runner Up 2011

Is it a star, is it a planet or is it a plane? A handy guide to identifying that bright object you saw last night.

Color-Full Moon © Nicolas Lefaudeux

Do we really need the Moon in the night sky? What is its actual purpose?

Jupiter with lo and Ganymede © Damian Peach, Astronomy Photographer of the Year Our Solar System and overall winner 2011

The planet Jupiter's more massive than all the other planets in the Solar System put together. It's a stormy mass of raging gas and metallic hydrogen.

RS39420302815_Winner_Infrared Saturn © László Francsics CUT.jpg

The best time to see and photograph a planet is when it is at 'opposition'. Find out more and check the key opposition dates for Mars, Jupiter, Saturn, Uranus and Neptune.