History of the Observatory

Østervold department

A drawing of what was then the NEW Astronomical Observatory on Østervold.

The Copenhagen University Observatory on Østervold was erected in the years 1859-1861 to accomodate the need for new buildings in which to place the University Observatory. Round Tower (Rundetårn) which had hosted the old University Observatory from 1642 to 1861, had become too small and partly also too unstable due to heavy traffic in Købmagergade below.

A cut through the Building. South to the left, North to the right.

The Observatory had several astronomical instruments:

A meridian circle in the west wing.
A passage instrument in the east wing.
Several pendulum clocks in the basement.
A dome with a 0.28m refractor for visual observations and a 0.2m photographic refractor.
A small magnetic observatory in the Garden House with earthmagnetic instruments.

The westmost part of the building was the Professor's Residence and the eastmost part was home to the Observer.

Today the 0.25m refractor is the only remaining part of the old instruments. A new instrument has been purchased in order to serve as a tool for student exercises - the NeST telescope, a 0.25m reflector of modern design and a small CCD detector.

Brorfelde department

The department in Brorfelde was inaugurated in 1953 and consisted of the main building with offices and electro-optical workshops, a large mechanical workshop and five guesthouses + several astronomical instruments.

The astronomical instruments here were:

The 0.77 m Schmidt telescope
A 0.40 m fotoelectric reflector
A 0.25 m fotoelectric reflector
A meridian circle


small picture of the Astronomical Observatory

The Observatory is now housed in the Rockefeller Building together with other departments and centers associated with NBIfAFG.

Source: Gyldenkerne & Darnell: "Dansk Astronomi gennem FireHundrede År".