What would the world look like without knowledge of the solar system? No one would land on the Moon and no research would be done on the effects of the sun's gravity on Earth. Furthermore, what if Galileo never studied the laws of moving objects or their mathematical effects? Many of today's advanced technologies depend on this fact. Galileo Galilei was an influential astronomer, physicist, and mathematician because of the complex discoveries he made and the knowledge he left to the modern world. He was one of the key figures in the information needed for the scientific revolution and played an important role in the Renaissance. He also contributed to physics, mathematics and astronomy through discoveries which he proved through numerous experiments. Many would consider this great man to be very significant in the studies he pursued. This is why he is listed at number 12 in Michael Hart's book, The 100: A Ranking of the Most Influential Persons in History. Galileo Galilei was influenced by the world he lived in and the Italian period of the 1500s. He was born on February 15, 1564 in Pisa Italy and lived during the Renaissance. In the book Galileo Galilei and the Science of Motion it is said that "at the time of Galileo's birth...Tuscany was controlled by the powerful Medici family, who had risen to power through wealth accumulated in banking and commerce » (Boerst 14). During this period, many artists and musicians were turning to more secular themes and works. Yet even with new secular themes, the Copernican theory was still not accepted by the Church. It was a doctrine that “had been judged heretical in 1616” (Pierre). This meant that the Central Church wanted to control the information made available to people, but subsequently lost some of its power. Additionally, Galileo was influenced to be a