Stjerneborg

Stjerneborg was a largely underground -scale observatory of the Danish astronomer Tycho Brahe. It was located near his palace Uraniborg Observatory on the island of Ven in Oresund. The royal architect Hans van Steenwinckel the Elder built Stjerneborg for Brahe in 1586, after he had to find that Uraniborg for his astrometric precision instruments was not big enough, and also was on unstable, sandy subsoil.

Brahe gave his new observatory the Latin name Stella Burgi. Both the Danish and the Latin name means Castle of the stars. The observatory was mostly built underground, so that the instruments rested on solid ground below the sand layers.

The instruments installed in Stjerneborg included a quadrant with 1.55 m radius and an equatorial armillary sphere, the angle could be measured with up to one minute of arc accuracy.

The underground lying areas were excavated in 1950/ 51 and later built over with a dome, take place in the public multimedia presentations.