Tycho Brahe in front of his house in Copenhagen. Tycho Brahe left Hven in 1597, bringing some of his instruments with him to Copenhagen, and entrusting others to a caretaker on the island. Shortly before leaving, he completed his star catalogue giving the positions of 1,000 stars. After some unsuccessful attempts at influencing the king to let him return, he finally acquiesced to exile, but he wrote his most famous poem "Elegy to Dania" in which he chided Denmark for not appreciating his genius. The instruments he had used in Uraniborg and Stjerneborg were depicted and described in detail in his book
Tycho Brahe architecture. When he realized that the towers of Uraniborg were not adequate as observatories because of the instruments' exposure to the elements and the movement of the building, he then constructed a second underground observatory at nearby Stjerneborg in 1581. The basement included an alchemical laboratory with 16 furnaces for conducting distillations and other chemical experiments. Unusually for the time, Tycho established Uraniborg as a research centre, where almost 100 students and artisans worked from 1576 to 1597. Uraniborg also contained a printing press and a paper mill, both among the first in Scandinavia, enabling Tycho to publish his own