Typical scientists. Fortunately for Tycho and Kepler, Hollywood has never let a lack of data get in the way of a plot. There’s no evidence that Antonio Salieri poisoned Mozart, and look what the movie “Amadeus” did for their album sales. The only difficulty for a screenwriter would be choosing an assassin from the competing candidates (and deciding between scholars’ Latin pronunciation of “Tee-ko” or the “Tye-ko” popularly applied to the lunar crater named after him). The movie would open, of course, with the duel in 1566 that cost the 20-year-old Tycho a good chunk of his nose (a sword fight possibly precipitated by an argument over mathematics, or maybe a mistaken astrological prediction by Tycho). Before long Tycho has a metal nose as well as an island with a castle and an observatory, financed by the king of Denmark and equipped with the most precise instruments yet built for tracking the planets and stars.

Tycho wins renown by identifying new stars, including a supernova, but after his royal patron dies, Tycho finds himself out of favor with the son and successor, Christian IV. Tycho goes to Prague and a new patron, Rudolf II, the Holy Roman Emperor. As he prepares to publish his decades of celestial observations, Tycho hopes to prove that all the planets except Earth revolve around the Sun, which in turn revolves around the Earth.

To help with the calculations, he brings in Kepler, a 28-year-old with his own weird model of the universe. Kepler, a devout Lutheran as well as a Copernican, believes that God created cosmic “harmony” by arranging the planets’ orbits around the Sun so that they’re spaced at distances corresponding to certain geometrical figures (the five “Platonic solids”). Tycho introduces Kepler to the emperor and lobbies for his appointment as imperial mathematician. But before Kepler’s appointment is formalized, Tycho suddenly becomes terribly ill after a banquet and dies 11 days later, at the age of 54.

What killed him? At the time of Tycho’s death, in 1601, the blame fell on his failure to relieve himself while drinking profusely at the banquet, supposedly injuring his bladder and making him unable to urinate. (Danes still sometimes invoke Tycho when they explain their need to excuse themselves during a meal.) Later medical experts discounted that and said some kind of kidney problem was more likely.

But then, in the 1990s, some hairs from Tycho were separately analyzed. Researchers reported elevated levels of mercury, including one brief high dose that was absorbed within 10 minutes during the final 24 hours of his life.