Galileo Galilei was one of the most influential scientists of the Renaissance period. He was a mathematician, physicist, astronomer and philosopher. It integrated and unified the independent sciences of mathematics and physics. The popular worldview, due to the overarching power of the Church, at the time was Aristotle's theory that the universe was geocentric, or that the Earth was at the center of the universe. Galileo went against this common belief and declared to the world that the Earth is not the center. This idea that humans are just a small speck in a limitless universe and that they are not the center of this limitless universe has frightened most religious leaders. The use of a telescope to study the sky had an extreme influence on his position on Copernicus's theory. Galileo was the first scientist to examine space using a fully functional telescope. Through his discoveries using the telescope, he agreed with those of Copernicus that the Earth was not the center of the universe. Galileo's many discoveries and his spectacular scientific and mathematical advances allowed him to defend the theory of heliocentrism in an attempt to oppose the Catholic Church; this resulted in his suit against the Church and ultimately his banishment. The Galileo affair began in 1610 when Galileo's Starry Messenger was published. The book mainly described his observations of the phases of Venus and the satellites he observed orbiting Jupiter. These discoveries would prove essential in this case. He would later use these observations to defend and promote Nicolaus Copernicus' heliocentric theory. His first discoveries, published in the Starry Messenger, were contested within the Catholic Church. In response to his book The Inquisition declared...... middle of paper ...... the feelings of ...... about the universe. Galileo feared people's retaliation for the truth about the universe because it contradicted the Bible. He went so far as to travel to Rome to plead with leaders to give people the opportunity to change their minds. Instead, Roman authorities recognized Copernicus' writings as heresy. Both Galileo and Copernicus were accurate in their theories, and the universal belief that the Earth is the center of the universe will never be the same. They revolutionized the beliefs of many people. This was difficult for society to understand because it was only taught that the Earth is the center and man cannot question it. Galileo completely opposed the belief of the Church and proved them wrong. He could have been considered an enemy or a hero. He didn't want to be either, but he just wanted the truth to be known..