There are millions of stars and planets in space. What's the difference between stars and planets? Stars can give out heat and light, but planets cannot.
The sun is one of the stars. Some planets are balls of rock and some are balls of gas. We live on the planet earth. The earth spins around once every day to give us day and night. The earth goes around the sun once every year to give us different seasons.
There are eight planets moving around the sun. We call the family of the sun and its planets the solar system. Mercury is the nearest to the sun, so it is very hot. It is the smallest planet. Venus is very bright and hot. It is the nearest to the earth. Mars is covered with orange-red desi and rocks, so it looks like a red star in the sky. It has seasons like the earth. Jupiter has more than 16 moons （卫星）and it is the biggest and heaviest planet. Saturn has more than 22 moons. The other planets, such as Uranus and Neptune, are all very far from the sun and very cold. We need a telescope（望远镜）to see them.
