Nicolaus Copernicus was born in Thorn, Poland on February 19, 1473. He was the son of a wealthy merchant. After his father's death, he was raised by his mother's brother, a bishop in the Catholic Church. Copernicus studied mathematics and astronomy at the University of Krakow. Through his uncle's influence Copernicus was appointed a canon (church official) of the Catholic Church. He used the income from the position to help pay for additional studies. Copernicus studied law and medicine at the universities of Bologna, Padua, and Ferrara in Italy. While he was studying at the University of Bologna, his interest in astronomy was stimulated. He lived in the home of a mathematics professor who influenced him to question the astronomy beliefs of the day.
After his return to Poland, Copernicus lived in his uncle's bishopric palace. While there he performed church duties, practiced medicine and studied astronomy. In Copernicus' time most astronomers believed the theory the Greek astronomer Ptolomy had developed more than 1,000 years earlier. Ptolomy said the Earth was the center of the universe and was motionless. He believed all other heavenly bodies moved in complicated patterns around the Earth. Copernicus felt that Ptolomy's theory was incorrect. Sometime between 1507 and 1515, he first circulated the principles of his heliocentric or Sun-centered astronomy. Copernicus' observations of the heavens were made with the naked eye. He died more than fifty years before Galileo became the first person to study the skies with a telescope. From his observations, Copernicus concluded that every planet, including Earth, revolved around the Sun. He also determined that the Earth rotates daily on its axis and that the Earth's motion affected what people saw in the heavens. Copernicus did not have the tools to prove his theories. By the 1600s, astronomers such as Galileo would develop the physics that would prove he was correct. Copernicus died on May 24, 1543.