Kepler knew his theories would be rejected by scientists, but he didn’t care. It had taken eons before anyone discovered how God had structured the universe, so Kepler figured he could wait another century or so to be proven right.

November marks the death of Johannes Kepler, one of the most important figures of the Scientific Revolution and a scientist who was motivated by his Christian beliefs. The significance of Kepler’s work can only be understood in light of what he faced and risked. The settled science of his day was that the Earth stood at the center of the universe. To challenge that meant to challenge the entire, accepted understanding of physics.

When Copernicus published On the Revolution of the Heavenly Spheres in 1543, he argued that the universe was centered on the sun rather than Earth. His motivation was to preserve the idea that planets traveled at a constant velocity in perfect circles. In other words, his motivation was more philosophical and aesthetic than it was scientific. Few scientists accepted these ideas that contradicted settled science. As a result, there were only a handful of committed Copernicans prior to 1600. Johannes Kepler was one of them.

Kepler was a devout Lutheran who planned to become a pastor. However, he excelled at mathematics and had an interest in astronomy. In seminary at the University of Tubingen, he became convinced by Copernicus and defended him on both scientific and theological grounds. After graduating in 1594, he took up teaching mathematics at the Protestant school at Graz (now the University of Graz) in Austria.

While in Graz, Kepler began to develop a theory about the number of planets and the relative size of their orbits. He found that his theory worked for all planets except Jupiter. Though he adjusted the theory to make it work, he was convinced the problem would be solved with better observations. As it turned out, the best observational astronomer in the world, Tycho Brahe, lived nearby.

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