(Please note: this post originally ran on December 27, 2017.)

It’s the birthday of one of the rock stars of astronomy, Johannes Kepler, born in 1571 in Weil der Stadt, Wuerttemberg, in the Holy Roman Empire of German Nationality. You may know him from such hits as Kepler’s First Two Laws of Planetary Motion (Astronomia Nova, 1609), Kepler’s Yet Another Law of Planetary Motion (Harmonices Mundi, 1619), and Let’s Discuss All of Heliocentric Astronomy in a Systematic Way (Epitome Astronomiae, 1621).

A sickly child, Kepler was born into a poor Lutheran family. He was a believer himself, yet ticked off the Lutherans by disagreeing on the doctrine of the Real Presence (it’s a communion thing) and was thus barred from taking communion. At the same time, he ticked off the Catholics by, you know, being Lutheran. Given when and where he lived, this officially put him between a rock and a hard place, and he had to relocate several times due to all the counter-Reformation brouhahas. Yet Kepler himself never felt conflict between his faith and his scientific work and once wrote to hotshot mathematician and astronomer Michael Maestlin, “I wanted to become a theologian; for a long time I was restless. Now, however, behold how through my effort God is being celebrated in astronomy.”

In his spare time from laying an entire theoretical foundation for orbital motion, Kepler figured out how vision works, wrote an essay called “On the Six-Cornered Snowflake” considered to be the first work on crystals, discovered several new polyhedra (surely a relief to those who were sick of the old polyhedra), and defended his mother from charges of witchcraft. (Show of hands: how many of your mothers have been accused of witchcraft? Really? Seriously?) He achieved all this in the midst of great personal difficulties, including the death of his first wife, the deaths of two children from that marriage, and the deaths of five of seven children from his second marriage—AND demanded of himself an unheard-of standard of empirical precision. (So the next time you’re having a rough day and you think, I can’t possibly be expected to finish this report when Starbucks is out of my favorite frappe-whatever and my incompetent boss keeps calling unnecessary meetings, ask yourself, what would Kepler do? Would he give up, crawl under an afghan, and binge-watch This Is Us while polishing off the holiday fudge? No, he would not. It’s something to think about.)

I like how nasa.gov ends their brief bio of Kepler’s life; you can just about hear them getting choked up: “Frail of body, but robust in mind and spirit, Kepler was scrupulously honest to the data.”

Have a good day, and stay scrupulously honest to the data.