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Johannes Kepler

Johannes Kepler (1571  1630) defined the three Laws of Kepler that
properly explained the motion of the planets around the Sun for the
first time. The three Laws of Kepler are:
 Each planet moves around the Sun in an orbit that is an ellipse,
with the Sun in one of the foci of the ellipse.
 The straight line segment from the Sun to the planet covers the
same amounts of area of the ellipse in the same amounts of time.
 The third power of the semimajor axis of the orbit of a planet is
proportional to the second power of the orbital period of the planet
around the Sun.