Johannes Kepler

An astronomer who revealed how the PLANETS ORBIT the Sun

Copernicus’s model, with the Sun at the centre of the Universe

Planetary puzzle

German astronomer Johannes Kepler initially agreed with Copernicus’s theory that the Sun is at the centre of the Universe, with the planets orbiting it in CIRCULAR PATHS. However, this did not explain the movements of the planets as seen from Earth.

Kepler’s model of the Solar System supported Copernicus’s theory. Kepler’s ideas greatly influenced later scientists – Isaac Newton used Kepler’s laws when developing his ideas about gravity. How he changed… the world

Redrawing the Universe

Kepler worked closely with leading Danish astronomer Tycho Brahe. Using Brahe’s data, Kepler CALCULATED that each planet moves around the Sun in an oval path, known as an elliptical orbit. He also observed that planets’ speeds vary according to their distances from the Sun. These ideas formed the basis of his laws of planetary movement.