Who was Galileo Galilei.

Galileo Galilei was a Italian physicist and astronomer. He was born in Pisa, Italy in 1564. He conducted experiments that contradicted beliefs during his time. He then became a professor of mathematics at the University of Pisa at the age of 25.

He taught theories about the universe which were against those of a man named Aristotle. Aristotle was a Greek philosopher in the 4th century B.C.E. One of Aritotle's beliefs was that objcts with more weight will fall faster than objects with less weight. The scientists during Galileo's time found that anything against Aristotles beliefs was suspect. So Galileo moved to teach in the University of Padua.

 In 1609, after hearing about the invention of the telescope, Galileo made his own telescope and examined the stars. He then made a book in 1610 about his finding called The Starry Messenger. Because of his findings, Galileo was appointed to become the court mathematician in Florence. He then wrote that he supported the theory of Nicholas Copernicus, that the Earth and other planets orbited the Sun. Which also contradicted Aritotle's belief and those of the Catholic Church that everything orbited the Earth.

Galileo was trialed in Rome in 1633 and forced to say that Copernicus was wrong. He was then sentenced to be confined in his house for the rest of his life. He then wrote another book about the motion of objects. Most of his theories were then proven correct after his death.