He was almost always ill and had an unhappy home life with difficult parents. Despite these difficulties, Johannes Kepler grew up to become one of the founders of modern science. His theories on how the planets moved shook the world.
For years, people had charted the paths of the planets but couldn’t make sense of them. They believed the orbits were circular. Kepler ignored these ideas and came up with his own very different ideas. It takes a great scientist to do that.
In 1609, he proved that the planets’ orbits around the Sun are elliptical, or egg-shaped.
That was Kepler’s first law of planetary motion. His second was that planets travel faster when closer to the Sun and slower when farther away.
In 1619, he came up with his third law. It was a way to calculate both the time it takes a planet to orbit the Sun and the average distance that planet is from the Sun.
Kepler also discovered a new star, figured out that tides are controlled by the Moon and improved the telescope. What’s more, this genius made his mark in the world of literature — he wrote the first work of science fiction!