Our planet is called the Earth. It moves around the Sun. It takes 365 days for our planet to go round the Sun. The Sun is a star. It gives us light and warmth. The sunshine passes through space and air and comes to our planet. Then one side of the Earth, which faces the Sun, has day. The other side has night.
Besides the Earth, there are 8 other big planets which move around the Sun, Their names are Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. Mercury is the smallest planet and Jupiter is the biggest one. The Sun and all the planets make the Solar System.
Astronomers say, they have found a new planet in our Solar System. They call it Sedna, but some of them dispute if it's really a planet.
There are many other stars in space. But they are far away from our planet. You can see stars only at night when the sky is dark. Large groups of stars make galaxies. Our galaxy is called the Milky Way. Galaxies are all different in shape. The Milky Way Galaxy is a spiral. Some groups of stars have their own names, for example, the Great Bear, the Little Bear.