SOURCE: "Brahe's Publication of His Hypothesis" and "Brahe's Discovery of Ursus's Plagiarism," in Three Imperial Mathematicians: Kepler Trapped between Tycho Brahe and Ursus, Abaris Books, Inc., 1986, pp. 17-44.

In the following excerpt, Rosen describes the publication, and the possible plagiarizing, of Brahe 's celestial system in 1588.

I. Brahe 's Publication of His Hypothesis

Tycho Brahe (1546-1601) was one of the greatest observational astronomers of all time. Some people think he was the greatest. But his innovation and skill in observing were not ends in themselves. Their ultimate purpose was to reveal the hidden structure of the universe. This secret had not been revealed, he felt, by the cosmologies he had learned as a student. Conscious of their defects, he devised his own hypothesis, the Tychonic system.

Two major celestial events shaped his thinking: the new star of 1572 and the brilliant comet of 1577. Around these spectacular heavenly displays he...