Tycho Brahe's observatory at Stjerneborg, Hven, 1584.
© Science Museum / Science & Society Picture Library
Coloured print by Johannes Blaeu of the Stjerneborg (Castle of the stars) observatory on the Isle of Hven between Sweden and Denmark. Built by Tycho Brahe, the Danish astronomer, in 1584, it was used by him to make observations for his new star catalogue. Brahe's first observatory, known as Uraniborg (Heavenly Castle), proved too small for his increasing activity and expanding battery of observing instruments. Unlike Uraniborg, the new structure was built of masonry and was mostly underground. Observations were made from five chambers containing single instruments under a rotating canopy to provide shelter from the wind and cold. Above ground within the building enclosure, four solid supports were provided for additional observing instruments.