What else did Isaac Newton do?

Newton had not published anything about the movement of the earth around the sun, despite having used his three laws of motion to formulate his ideas of universal gravitation to describe the movement of the moon round the earth. As a consequence of an argument between Sir Christopher Wren, Robert Hooke and Edmond Halley, the latter went to see Newton in Cambridge. Newton told Halley that the planets moved in ellipses and that he had worked this out mathematically. Halley asked to see the proof, but Newton could not find his papers and it took him three years to write this out, in a book called Principia.

Isaac could not achieve promotion, nor become master of a college at Cambridge because he was a Unitarian and did not accept the doctrine of the Trinity. Hence in 1696, he left Cambridge to go to London as Master of the Royal Mint. In 1703, after Robert Hooke's death, Newton became president of the Royal Society. He published his book on light: Opticks in 1704 and was knighted by Queen Anne in 1705.

Isaac Newton died in London on 20th March 1727. He is buried in Westminster Abbey.