The Universe contains everything that exists, including you, the stars, the galaxies and even time itself. It is mostly empty space, with clumps of stars and gas separated by huge amounts of nothingness. In between the galaxies and clusters of galaxies, you would have to travel a very long way to find even a tiny bit of dust. The distances between these galaxies and clusters are getting bigger all the time because the Universe is getting bigger. Astronomers think that the Universe is about 15 billion years old.
Click on the links below to find out more about the Universe.
Authors: Carolyn Brinkworth and Claire Thomas
Last updated: July 2001