James Bradley

James Bradley FRS (1693 – 13 July 1762) was an English astronomer. He was born in Sherborne, Gloucestershire, England. Bradley was educated at Northleach Grammar School and at Balliol College, Oxford. He received a Bachelor of Arts degree in 1714 and a Master of Arts in 1717. 
He became a member of the clergy and received an income at Bridstow in Herefordshire. Because of his friendship with Edmond Halley, in 1718 he was elected as a fellow of the Royal Society. He gave up his living at Bridstow to become a professor at Oxford in 1721. Bradley succeeded Edmond Halley as Astronomer Royal at the Royal Observatory, Greenwich in 1742. He held this post until his death in 1762.
In 1729 he published his discovery of the aberration of light (also called astronomical aberration). This was he first observational proof of the Copernican Hypothesis that the Sun is at the centre of the Solar System and not the Earth. He noticed a motion in the stars that did not fit the accepted pattern of the time. What he discovered was stellar aberration. In 1748 he published his discovery. That same year he was awarded the Copley Medal from the Royal Society for his discovery.