On the history of the Great Refractor

  • 1874 Founding of the Potsdam Astrophysical Observatory (AOP).
  • 26 August 1899 The Great Refractor is put into service as the AOP’s main instrument.
  • April 1945 The building and the mechanical components of the Great Refractor were severely damaged in an air attack.
  • 1953 Carl Zeiss Jena restored the instrument and modernised it in the process.
  • 1968 Observational operations (primarily a programme for observing binary stars) had to be suspended.
  • 1986–1990 Refurbishment of the dome’s outer shell; removal of the severely damaged interior cladding
  • 1993 Refurbishment of the floor.
  • 1994–2002 Exhibition ‘From the Great Refractor to the Einstein Tower’ to mark the 70th anniversary of the inauguration of the Einstein Tower.
  • 19 March 1997 Founding of the ‘Förderverein Großer Refraktor Potsdam e.V.’ (Friends of the Great Refractor, Potsdam).
  • July/August 1999 Restoration of the telescope and observation chair in accordance with heritage conservation standards.
  • 27 August 1999 Celebration to mark the 100th anniversary of the Great Refractor.
  • 2000 Repainting of the outer dome shell.
  • April 2003 Begin of restoration work on the telescope by 4H-Jena Engineering
  • 17 June 2005 Return of the Great Refractor, in separate parts, to the dome
  • 31 May 2006 Ceremonial re-inauguration of the Great Refractor
Gray image of a long telescope in a dome

The Great Refractor about 1905

Credit: Förderverein Großer Refraktor Potsdam e.V.
Dome under construction with scaffolding

The building for the refractor under construction

Credit: AIP Archive
Rusty telescope

Condition prior to restoration

Credit: Förderverein Großer Refraktor Potsdam e.V.
A dark green telescope beneath a dome with reddish-brown wooden panelling

After the restoration 2006

Credit: Förderverein Großer Refraktor Potsdam e.V.
A round building with a dome, surrounded by green trees

The building after its refurbishment in 2017

Credit: Förderverein Großer Refraktor Potsdam e.V.