Galileo Galilei was born in Pisa, Italy, in 1564. His father taught music while his mother cared for kids at home. The family was not wealthy, but Galileo's parents paid for him to go to school.
At first Galileo planned to become a doctor, but he changed his mind. He liked a different kind of science—physics. In Galileo's time, not much was known about how objects moved. Centuries earlier, a Greek (希腊人) named Aristotle had written down his ideas about movements, and everyone seemed to believe them. Galileo questioned those ideas and did experiments (实验) that showed how things really worked. For example, Aristotle thought that a heavier object would fall faster than a lighter one of the same size and shape. No one had ever really tested this idea. It just seemed to be true. Then Galileo came along, dropped two balls from a high tower, and discovered that they hit the ground at the same time!
In later years, Galileo became interested in how the stars and planets move. He watched the sky with a telescope (望远镜) he built himself. Once again, he saw things no one had ever seen before. For example, he saw that the moon was not smooth. Then he noticed that the sun had spots (斑点) that seemed to move. Galileo realized from his observations (观察) that the earth was moving around the sun. A Polish (波兰的) scientist named Copernicus had said this recently, but no one believed him. Galileo knew that Copernicus was right. Unluckily, Galileo's announcement got him into trouble with the Catholic Church. The Catholic Church said that the earth was at the center of the universe (宇宙) with the sun traveling around it. This was what people had long believed, but Galileo said it was untrue. So he was sent to jail (监狱) . He was soon set free, but for the rest of his life he had to stay in his house and yard
Galileo died in 1642, but his work helped to change the world. He is sometimes called the "father of modern science" because he showed us how important it is to look carefully at things and to test out ideas with experiments.
