Johann Kepler and planetary motion

I admire Johann Kepler among many scientists paving the way for Scientific Revolution in modern history.
In Linz, it seems that they also admire Kepler greatly. Johannes Kepler Universität is located in Linz.

Kepler's Three Laws
Kepler's three laws of can be described as follows [1]:

1- All planets move in elliptical orbits, with the sun at one focus. 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)
2- 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)
3- 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. (The Law of Harmonies)

[1] http://www.physicsclassroom.com/class/circles/Lesson-4/Kepler-s-Three-Laws