# What Is Kepler's Third Law?

Have you ever wondered how the planets move in our Solar System?

Well, a mathematician named Johannes Kepler wondered the same thing hundreds of years ago.

Kepler used maths to come up with a set of rules to describe how the planets of our Solar System move. Watch this video and discover what Kepler's Third Law (and later discoveries about gravity) tells us about how the planets move around the Sun.