Over millions of years, hot clouds of gass called nebulae grow until they explode and form huge, blazing balls of fire. This is how stars are born. Our own sun is a star. Eventually, like all stars, it will run out of fuel and die. Don't worry though - this won't happen for another 4 billion years!

Stars are sources of light. This is the reason they shine so brightly in the sky. The moon, planets and comets also shine, but they don't give out their own light. They just reflect it from the sun.

Stars are very, very far away. In fact, when their light reaches our eyes, we sometimes see them as they were thousands of years ago! Our sun is the nearest star to Earth, but it is still about 150 million km away! It is part of the Milky Way galaxy, a white band of stars that stretches across the night sky. There are more than 100 billion stars in the Milky Way and many of them, like our sun, have planets that orbit around them.

Constellatins are groups of stars. If you draw lines between them (and use a lot of imagintion!) they sometimes look like objects, animals or people. The ancient Greeks thought that Orion looked like a giant hunter with a sword attached to his belt!

As the earth moves around the sun, we see the constelltins in different positions in the sky at different times of the year. In the same way, the whole sky seems to move towards thewest as the earth rotates on its axis throughout the night.