Space and Time
Out on a spiral arm of the galaxy we call the Milky Way lies an inconspicuous star. To a casual observer it might look just like any of the other 400 billion or so stars in the galaxy. To us, however, it's home. We call that particular star the Sun and it's the centre of our solar system.
Our solar system is made up of the Sun, the nine planets and their moons, comets and asteroids.
The four planets closest to the Sun - Mercury, Venus, Earth and Mars - are called the terrestrial or rocky planets, because they have solid, rocky surfaces. The four planets beyond these - Jupiter, Saturn, Uranus and Neptune - are called gas giants. These planets have no solid surfaces and are mostly made up of various gasses such as hydrogen, helium, methane and carbon dioxide. Even further away from the Sun is the tiny, cold planet Pluto, orbiting at the edge of the solar system.
Here you can find out more about the planets and all the other elements that make up our solar system. Follow the links in the navigation panel to explore our corner of the Universe.
Images, information and videos courtesy of NASA.