Johannes Kepler (1571-1630), one of history’s geniuses, laid the foundations of modern celestial physics with his laws of planetary motions, the groundwork for Newton’s universal law of gravitation. He was an endless font of theory and speculations, much of it mystical and misguided, some of it brilliant, Yet if it hadn’t been for the Brahe’s planetary data, Kepler would be a mere footnote in today’s science books. Tycho Brahe (1546-1601) was the most famous astronomer of his era, one of the first systematic empirical thinkers, and a founder of the modern scientific method. Brahe recorded over forty years of naked-eye observations of the planets and the stars with ingenious instruments of his own invention; those observations were so extraordinarily precise that only telescope could surpass them over a century later. And the fact is, Brahe refused to share his data with Kepler.

Brahe took Kepler as his assistant on one specific project because of Kepler’s mathematical skills and in spite of some previous personal conflicts. Kepler’s request to access the main bulk of data was repeatedly denied. Brahe was surely aware of the Kepler’s dark side of rage, fear, jealousy and an obsession to possess the planetary observations as his own but he was not cautious enough: Kepler lived with him in a same house for the last eighteen months of his life. After Brahe’s sudden and unexpected death on October 24, 1601, age 59, there were rumors of poisoning but it was not until the 1996 PIXE (particle-induced X-ray emission) analysis of the Brahe’s hair strands that the poisoning by mercury was confirmed: the mercury must have been given to Tycho Brahe thirteen hours before he died.