Declaration of the South African Astronomical Observatory as a National Heritage Site

On December 21, 2018, the South African Heritage Resources Agency(SAHRA) officially declared the South African Astronomical Observatory as a National Heritage Site.

This is a very exciting development for the SAAO, recognising the incredible achievements and their significance over the past two centuries, and will ensure this heritage is preserved. The declaration is made with the understanding that we are to remain a working site and that the Heritage status will not curtail our primary function as a world-class observatory.

Image Credit: Illustrated London News, 21 March 1857/Ian Glass

SAHRA released the following statement along with a statement of significance, please find attached the entry in the Government Gazette:

“SAHRA identified the site as having qualities so exceptional that it is of special national significance and warrants declaration as a National Heritage Site.”

Statement of Significance

The South African Astronomical Observatory in Cape Town has played a highly significant scientific role over time as the oldest permanent observatory in the Southern Hemisphere. The site offers an overview of the history of astronomy both locally and internationally. It is a “living site” with almost 200 years of history while still retaining its prominence in the international astronomical community.

Contributions to astronomy from the site range from some of the first accurate measurements of the distance to a star(Alpha Centauri), first catalogues of the principal southern stars, the first photographic survey of the sky, accurate measurements of the distance to the Sun( a value that became the benchmark to measure all other cosmic distance and represented a paradigm shift in astronomy), development of spectroscopy, remeasurement of Lacaille’s Arc of Meridian, establishment of the true shape of the Earth in the Southern hemisphere and the first accurate geodetic surveys of southern Africa.

Architecturally, there are several buildings of historical value and not only reflect the changing architectural styles over the nineteenth century but also have a considerable scientific value due to their contributions to the field of astronomy. The Main Building(a Georgian Building) – designed by the British naval architect, John Rennie, and completed in 1828, the heliograph – the oldest dome on the site and which runs on cannon balls, and the McClean Telescope Building – designed by Herbert Baker.

The range of scientific object related to the observatory as a collection is integral to the scientific value of the site. Some of the instruments within structures have been used with varying degrees of continuity and consistency for over 180 years.


Daniel Cunnama:, 0212015169