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Unisa online - Remember the 9 inch Reunert Telescope on top of the TvW building


The 9 inch Reunert Telescope back at the Johannesburg Observatory

Remember the 9 inch Reunert Telescope on top of the Theo van Wijk building?

On Friday 31 July 2009, the College of Science, Engineering and Technology and the South African Agency for Science and Technology Advancement (SAASTA) were two of the main collaborators at the provincial launch of National Science Week where the Reunert 9 inch telescope was officially handed back to SAASTE. 

The Reunert Telescope was used in South Africa at the Johannesburg Observatory by Robert Innes in 1915 to discover Proxima Centauri, the closest Star to our Sun.

In 1972, when Unisa staff moved into the newly completed Theo van Wijk building on the Muckleneuk campus, the Reunert telescope was installed on the roof of the building. This 9 inch refracting telescope was donated to the Astronomy section of the Mathematics Department at Unisa by the Republic Observatory in Johannesburg. The telescope was installed and operated by Mr Wolterbeek, the sole member of the Astronomy Section at that time. For several years, this telescope was used to host public viewing evenings, for student training and by Mr Wolterbeek to do his observations of double stars.

In 1992, a new observatory was opened on the Unisa campus, which is equipped with a modern 14 inch computer-controlled telescope. Viewing evenings and student training now use this easily accessible facility. Mr Wolterbeek no longer has the strength or energy to use the Reunert telescope and so its only function is to collect dust.

Although the Reunert telescope is not the most convenient instrument to use for observational astronomy these days, the telescope has a lot of historical significance. It  was used by Mr Innes at the then Union Observatory (the name was changed to the Republic Observatory in 1961) to make a set of observations on a star known as Proxima Centauri, which Innes established is the nearest star to our Solar System. To this day, nearly a century later, Proxima Centauri still holds the record as being our nearest stellar neighbour.

The SA Agency for the Advancement of Science and Technology (SAASTA) is a business unit of the National Research Foundation (NRF) whose purpose is to promote the public understanding of science and technology in SA.  SAASTA now owns the site and facilities at the Republic Observatory, which they use to house a science museum and run educational programmes. They would now like the 9 inch Reunert Telescope to be returned to its dome on the Observatory site so that they can preserve this important piece of South African astronomical heritage.

The Directory of SAASTA, Ms Beverley Damonse, visited Unisa recently to look at the telescope and is willing to pay the costs associated with dismantling the telescope here at Unisa and having it transported through to Johannesburg where it will be re-installed in its original dome. Rather than collect dust in Pretoria, this telescope will be on display and its role in South African astronomical discoveries will hopefully inspire a new generation of young scientists.

Prof Derck Smits said many of Unisa’s staff who have been here since before the 1990s might have gone to the rooftop observatory to view Halley’s Comet in 1986 or for general viewing evenings.



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