Union Observatory

Union Observatory
Alternative namesJohannesburg Observatory Edit this at Wikidata
Observatory code 078 Edit this on Wikidata
LocationObservatory, Johannesburg, South Africa
Coordinates26°11′3″S 28°04′27″E / 26.18417°S 28.07417°E / -26.18417; 28.07417
Altitude1,808 metres (5,932 ft)
Established1903; 121 years ago (1903)
Closed1971
Websiteassa.saao.ac.za/sections/history/observatories/rep_obs/ Edit this at Wikidata
Union Observatory is located in South Africa
Union Observatory
Location of Union Observatory
[edit on Wikidata]
Photo of comet Mellish obtained with the Franklin Adams star camera of the Union Observatory on June 6, 1915, with an exposure of ninety minutes. The position of the comet was then R.A. 22h. 35m., declination 70° 18′ south.

Union Observatory, also known as Transvaal Observatory, Republic Observatory and Johannesburg Observatory (078), is a defunct astronomical observatory in Johannesburg, South Africa that operated from 1903 to 1971. It is located on Observatory Ridge, the city's highest point at 1,808 metres altitude in the suburb Observatory.[1][2]

The observatory and its former annex, the § Leiden Southern Station, are known for the discovery of 6,000 double stars and for Proxima Centauri, made by astronomer Robert Innes. At the observatory, 578 identifications of minor planet were made, a record number at the time.[1] The Minor Planet Center credits the observatory as the site where 147 minor planets were discovered by astronomers Harry Wood, Cyril Jackson, Hendrik van Gent, Ernest Johnson, Ejnar Hertzsprung, Jacobus Bruwer and Joseph Churms (see § List of discovered minor planets).[3]

  1. ^ a b Cite error: The named reference ASSA-new was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference ASSA-archive-full was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference MPC-Discoverers was invoked but never defined (see the help page).