How Kepler's Worst Idea Led To Cosmic Truth

This is the mysterium cosmographicum. It's simple. It's beautiful. It even predicts the distances between the first six planets. And it's wrong. But here's why that's okay. [Music] Hey crazies, we're all human. I I think we all make mistakes. We've all come up with plans or ideas that turned out to be not so great. It's part of the human experience. But one of my favorite things is when bad ideas lead us to good ones. And it happens in science more often than you'd think. This mysterium cosmographicum is one such example. It was developed by a guy named Johannes Kepler in 1596, over a decade before the proper laws we'd eventually name after him. Astronomy teachers like to skip to those later laws and then paint Kepler as this pure mathematician with no character depth. But like anybody, he was multiaceted. He may have been a mathematician and astronomer, but he was also an astrologer, a husband, a father, and a deeply religious man. These all come together to create the lens through which he saw the world. Now, that's not to say that Kepler didn't have opposing opinions. For example, he was Lutheran when most people were Catholic, which certainly made his life difficult. He also had a problem with the established philosophy about the universe. The common belief at the time was that the Earth was at the center of the universe and that all other objects go around it. I mean, why wouldn't the Earth be at the center? It's obviously the most important, right? But my boy was skeptical. He knew the path of planets like Mars would periodically do this weird wiggle in the sky when you track them over a long time. For an earth- centered model to display motion like that, you had to add these things called epicycles that cause the orbits to curl up. It was a mess. As far as Kepler was concerned, there was no way a divine being would create a universe so complicated. He thought God would create a universe that was simple and geometric. First, it should definitely include the Platonic solids.