Long, long ago people thought that the sun went around the earth. In some countries, people said that the sun was a god(神). They thought that he drove across the sky each day on a golden (金色的) horse. But now we know the earth goes around the sun. Today men know how far it is for the earth to go around the sun. They tell us that the earth travels over 1000miles (英里)a minute on its way around the sun. The sun is really a star. It is much bigger than the earth and it is very hot. Some people have been to the moon, but we know that no one can ever get to the sun. It is too hot for people to live anywhere near it. The sun is 300, 000 times heavier than the earth and more than a million(百万) times larger.

Why can’t people live in the sun Because ______.