Galileo Galilei (1564-1642) is best known for his theories of celestial motion, which contradicted the view that the Earth was in the heavens and that all the other heavenly bodies revolved around it. Basing his ideas about celestial motion on his observation of the planets and their moons through a telescope, Galileo realized that the ancient theories of Ptolemy (which placed the Earth at the center of the universe) were incorrect. Through these observations, Galileo was able to confirm the theories of Nicholas Copernicus who made similar theories, but lacked the evidence necessary to prove them. In 1632, Galileo published his Dialogues on the Two Chief Systems of the World and immediately put himself in trouble with the Roman Catholic Church. On September 23 1632, he was summoned to Rome and put on trial. Following the verdict of the Inquisition, he was forced to disavow his beliefs regarding the Copernican theory and the motion of the earth. The original verdict condemned him to life in prison, but was later changed to house arrest, a sentence that detained him to his home until his death. His book was also later banned by the Catholic Church and only in the 1990s, did the Church once again grant its public display.
This painting by Cristiano Banti (1857) depicts Galileo’s famous trial in Rome which set a boundary between religion and science.