Every elementary school student learns about Sir Isaac Newton, the man who famously discovered gravity by having an apple drop from a tree and hit him on the head. His work on classical mechanics, optics and mathematics made landing a man on the moon possible -- among many other things.


Isaac Newton was born in Woolsthorpe, Lincolnshire, in England on January 4, 1643. He father worked as a farmer but died three month before Newton was born. His grandparents raised him after his mother remarried.


In 1661, Newton enrolled in Cambridge University. While at school, he studied mathematics, optics, physics and astronomy. However, a plague epidemic closed the university down in 1665. This forced Newton to returned to his hometown of Woolsthrope, though he continued to study optics and mathematics. During this time, he also invented calculus, the branch of mathematics devoted to change.

The Apple Story

Most people know the popular story that Newton discovered gravity when an apple fell on his head as he sat under an apple tree. While a fun and entertaining story, he actually had the epiphany about gravity when he looked out the window and saw an apple drop in his garden.

Law of Universal Gravity

Newton discovered the law of universal gravity, which states that attractive forces occur between any two pieces of matter. Gravity keeps everything fastened to the earth. It also keeps the moon and other planets in orbit. Along with astronomer Edmund Halley, Newton published “The Mathematical Principles of Natural Philosophy” in 1687 to explain gravity.

Laws of Motion

This scientist also put forth the three laws of motion. According to the first law of motion, an object will remain motionless until struck by a force. The second law states that the greater the mass of an object, the greater the force needed to move that object. The third law says that there is an equal and opposite reaction for every action.


In 1704, Newton published “The Opticks” which explained his discovery that white light is made up of the same colors that you see in a rainbow. This discovery led to the modern study of optics.

Newton's Many Jobs

Newton worked as more than just a scientist in his life. He worked as a Lucasian professor of mathematics at Trinity College, as a parliament member for Cambridge University, and a warden at the Royal Mint in London, where he fought against corruption and inefficiency. In 1703, he became president of the Royal Society.


In 1705, Isaac Newton became Sir Isaac Newton, when Queen Anne knighted him for all his contributions to science.


Newton took his Christian religion seriously; he wrote more work on theology than science. He also calculated the exact date of Jesus Christ’s Crucifixion as April 3, 33 A.D., and estimated that the Apocalypse could come as early as 2060 A.D.


While still president of the Royal Society, Sir Isaac Newton died on March 31, 1727 at age 84. He is buried in Westminster Abbey in London.