Isaac Newton 1643-1727

Isaac Newton 1643-1727

Apples or comets - what helped Newton develop his theory of gravity?

Famous for:

  • Gravity! Newton was the first to develop a theory of gravitation
  • Newton's three laws of motion
  • Working with optics, light and colour - he showed that the spectrum could be formed by splitting white light through a prism
  • Developing the theory of calculus - much to the dismay of maths students everywhere

Newton often said that his theory of gravity was inspired by watching an apple fall from a tree. Did it really happen like that? Newton probably exaggerated this story, although seeing apples fall from trees may have influenced his ideas.

Scientists now think that the appearance of a comet in 1680 and 1681 prompted Newton's theory of gravity. In 1680, the comet was visible for a long time, before disappearing behind the sun. In 1681, a comet appeared again! Was it the same comet in 1680 and 1681? If so, the comet's path must have bent a lot. If the sun could bend the path of a comet, Newton realised there had to be an unseen force at work. He called it gravity. His idea didn't come from an apple falling from a tree, but from a comet passing behind the sun.


A comet - not an apple - influenced Newton's theory of gravity

Newton's ideas on gravity were the foundation of modern physics. He is widely regarded as one of the world's most influential scientists.

To find out more about Newton's work on light and colour, go to Can you make a rainbow disappear? and All the colours of the rainbow.

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