When I was young, I wanted to be an astronaut. I often imagined being in space. It seemed mysterious to me. Now that I’m older I am more knowledgable about space.

　When we talk about the universe, we mean not only the earth, the sun, the moon and the stars, but also all the things that are too far away to see.

　In the past 50 years or so, scientists have been able to “see” farther into the sky. They have found many “new” stars. Those stars are not really new; in fact, they have been there for millions of years.The sun is actually a star.

　Millions of other stars are even bigger and brighter than our sun but they look small because they are so far away. You can’t see them in the daytime.

　But if you go out at night, you’ll be able to see thousands of them.The earth is one of the sun’s planets, and the moon is our satellite. It is our nearest neighbour in space, and men have already visited it. No man has traveled farther than the moon, but unmanned spaceships have reached other planets.

　Many countries have set up man-made satellites to circle the earth. With their help, people have done a lot of reseach in many fields of science.