16th-century astronomer Tycho Brahe was not murdered
Scientists exhumed the astronomer's body in 2010 in an attempt to discover what exactly had killed the man back in 1601. Hair samples taken during an earlier exhumation had tested positive for mercury, a highly toxic element that's always a great way to kill your enemies.
The more recent study, however, found that Tycho's beard contained mercury levels similar to those seen in modern humans, according to BBC News. In other words, it wasn't enough to kill the guy. This means that Tycho Brahe was probably not murdered by his patron, the King of Denmark, or by his assistant, Johannes Kepler.
Working in the late 16th century at a vast observatory built on his own island, Tycho was able to produce a huge map of the stars. These accurate observations later helped to prove that the Earth revolved around the Sun and not vice versa.
In the absence of a good murder story, we return to the traditional -- but equally good -- account of Tycho Brahe's death at the age of 54. As a nobleman as well as an astronomer, Tycho frequently attended royal banquets and such. And you didn't leave Renaissance-era royal banquets early. That is why, although he desperately needed to pee, the astronomer did not excuse himself from the table.
His bladder then ruptured and Tycho Brahe died of infection 11 days later. Who needs murder when you have a death like that?