ycho Brahe, the famous 16th century astronomer, lived on Ven for 21 years. He had received this as a fiefdom and built what was probably the most powerful observatory of the time. Without a telescope, but with excellent angle measuring instruments. Later, when the island was taken away from him by the king for improper behavior, Tycho Brahe went to Prague and met the young Kepler there, who became his assistant. He evaluated Tycho Brahe's observations after his death and used them to prove that the earth revolves around the sun and not the other way around. Tycho Brahe's death was unexplained for a long time. He collapsed at the banquet table of Emperor Rudolph II and died shortly afterwards. According to legend, his bladder burst. He drank too much wine and did not go to the toilet out of politeness to the emperor who was present. Maybe he was poisoned too. Was it Kepler? Shortly after Brahe's death, Kepler's groundbreaking observation was published. This was suspected for a long time. Because Tycho Brahe had always only handed over incomplete data sets to him, letting the assistant dance to his tune as long as he was in charge, but he had ordered that Kepler should analyze all of his data after his death. The grave was opened several times to determine the cause of death. In 2012, bone and hair samples were used to rule out poisoning.