Johannes Kepler wrote Astronomia Nova (1609) in a singleminded drive to sweep away the ancient and medieval clutter of spheres and orbs and to establish a new truth in astronomy, based on physical causality. Thus a good part of the book is given over to a nontechnical discussion of how planets can b[...]

Johannes Kepler (1571-1630) was one of the most admired astronomers who ever lived and a key figure in the scientific revolution. A defender of Copernicus' s sun-centered universe, he famously discovered that planets move in ellipses, and defined the three laws of planetary motion. Perhaps less well[...]

The brilliant German mathematician Johannes Kepler (1571-1630), one of the founders of modern astronomy, revolutionised the Copernican heliocentric theory of the universe with his three laws of motion: that the planets move not in circular but elliptical orbits, that their speed is greatest when nea[...]