Kepler Discovers How Planets Move
Credit: Johnnes Kepler Gesammelte Werke , C. H. Beck, 1937
Johannes Kepler used simple mathematics
to describe how planets move. Kepler was an assistant to the most accurate
astronomical observer of the time, Tycho Brahe.
Kepler was able to use
Brahe's data
to show that planets move in ellipses around the Sun
(Kepler's First Law),
that planets move proportionally faster in their
orbits when they are nearer the Sun (Kepler's Second Law), and that more
distant planets take proportionally longer to
orbit the Sun (Kepler's Third
Law).
Kepler lived from 1571 to 1630,
during the time of discovery of the telescope. Kepler was one of the few vocal supporters of
Galileo's discoveries and the
Copernican system of planets orbiting the
Sun instead of the
Earth.