Kepler’s three laws of planetary motion are: (i) The path of the planets about the sun is elliptical in shape, with the center of the sun being located at one focus (The Law of Ellipses).
(ii) An imaginary line drawn from the center of the sun to the center of the planet will sweep out equal areas in equal intervals of time (The Law of Equal Areas) and (iii) The ratio of the squares of the periods of any two planets is equal to the ratio of the cubes of their average distances from the sun.