Stars

When you look outside at night you can see many beautiful stars. If you are in a dark country area you might see as many as 3000 of them. In the city you can't see nearly as many, but they are still pretty. There are several different kinds of stars in the sky. Some are very big. A couple have been found that are 100 to 200 times bigger than the sun. At the end of their lives these large stars can stretch themselves out past the orbit of the planet Uranus. Some very old stars are smaller than the Earth. Scientists study stars, and place them in groups based on how they are alike, and how they are different.