Observatorium Tusculanum

Observatorium Tusculanum, near Vridsløsemagle west of Copenhagen, was the countryside observatory built in 1704 by the great Danish astronomer Ole Rømer. Though it stood for only a few years, it made history as the first observatory in the world equipped with a meridian circle - an instrument Rømer himself invented.

About Observatorium Tusculanum

Tusculanum was Ole Rømer's private observatory, built about 17 kilometres west of Copenhagen, Denmark - the first observatory established outside the Danish capital. It is best known for housing the world's first meridian circle, a precision instrument of Rømer's own design for timing the passage of stars across the meridian.

History

Rømer founded the observatory in 1704, but it fell into disrepair soon after his death in 1710 and that of his assistant L. Skive in 1711, collapsing from neglect. Its instruments were moved to the Round Tower observatory in Copenhagen in 1716–1717, and most were later lost in the great Copenhagen Fire of 1728. The site itself lay forgotten until its remains were rediscovered in 1978.

Location & getting there

The site sits near Vridsløsemagle, about 17 kilometres west of Copenhagen, Denmark, and is reachable by S-train or bus 116 from central Copenhagen.

Visiting Observatorium Tusculanum

Today the site is cared for by Kroppedal Museum, Denmark's museum for the history of astronomy, which manages access and interpretation of the remains. Check with Kroppedal Museum for current visiting details before you go.

See your named star from here

Ole Rømer built his meridian circle to fix the exact position of stars in the sky - much the same idea behind the right ascension and declination on a Star Register certificate. Name a star or explore the catalogue to see the tradition continue.