阅读理解
How much do you know about the universe? In the huge universe, there is the Galaxy and many other galaxies. In the Galaxy, there is the Solar System and lots of other stars. In the Solar System, there is the sun, the earth and seven other planets. As we know, the eight planets go around their star —the sun. In our Earth—moon System, the moon goes around the earth. And because our earth keeps turning around the sun all the time, we have day and night. When our part of the earth turns to the sun, it is day. When our part of the earth turns away from the sun, it is night.
Just because the moon is closer to the earth than the sun, it looks much bigger than the sun. The sun is big enough to give out very strong light. The moon itself can't give any light at all, but it looks quite bright, too. In fact, the light from the moon comes from the sun. Although, the moon looks much bigger and brighter than the sun and other stars, in fact, all the stars are much bigger and brighter than the moon. They look smaller than the moon also because they are farther away from us. It's clear that big things will look smaller when they are farther, and small things look bigger when they are nearer.
So far, we have traveled to many other planets in the universe. But scientists haven't discovered any living things on any other planets. Scientists haven't discovered any other planets with a good environment. They aren't sure if there is any water and air for living things to live on other planets. People always ask the question: Is there anyone out space? Our scientists haven't got a clear answer either. Some people think it will be a secret for a long time. But we believe we can solve the problem some day.
Exploring our Solar System and the universe is a great national project to some countries. Our Chinese scientists are also trying to send spaceships with astronauts to those planets and even the universe. At 9:00 a.m. on October 15th, 2003, a Chinese astronaut called Yang Liwei was sent up to space. He stayed there for hours and got back to the earth at 6:00 a.m. the next day. It was the first time for Chinese to have a space travel.