1546 – Born on December 14th in Knudstrup, Skane, Denmark (now Sweden). Tycho Brahe is probably the most famous observational astronomer of the sixteenth-century. 1562 – After three years at the University of Copenhagen, he spent much of the period traveling in Germany, studying at the Universities of Leipzig, Wittenberg, and Rostock, and working with other scholars in Basle, Augsburg, and Kassel. 1566 – It was in Rostock that he lost part of his nose in a duel, and subsequently wore a prosthesis. 1572 – The appearance of a "new star" (in fact a supernova) prompted Tycho’s first publication, which was issued by a Copenhagen printer. 1574 – Gave some lectures on astronomy at the University of Copenhagen. Already he was of the opinion that the world-system of Copernicus was mathematically superior to that of Ptolemy, but physically absurd. 1576 – His permanent relocation to Basle, which he considered the most suitable place for him to continue his astronomical studies, was forestalled by King Frederick II, who offered him in fief the island of Hven in the Danish Sound. 1588 – Tycho issued from his press a work on the comet which had appeared, causing a flurry of other publications. 1596 – He published a volume of his correspondence with another noble-astronomer, Wilhelm IV of Hesse-Kassel, and Wilhelm’s mathematician Christoph Rothmann. 1597 – The erosion of Tycho’s funding and standing following King Christian IV’s attainment of his majority caused the astronomer to leave Denmark. 1598 – Other works begun on Hven were the Astronomiae instauratae mechanica, an illustrated account of his instruments and observatories, and the Astronomiae instauratae progymnasmata, which contained his theory of lunar and solar motions, part of his catalogue of stars, and a more detailed analysis of the supernova. 1599 – He settled near Prague, having been appointed Imperial Mathematician by Emperor Rudolph II, and was joined by Johannes Kepler the following year. 1601 – He died of uraemia on the 24th of October, at Benatky, and was buried in the Týn Church, Prague.