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More Than a Pinch of SALT in the Southern Hemisphere
by Duane Dunkerson

A substantial tradition of gathering astronomical data in South Africa is to be continued with the South African Large Telescope (SALT).

The Royal Observatory at the Cape of Good Hope was established in the 1820's. Astronomical work there for many years concentrated on preparing star catalogues. In 1972 South African observatories were merged into the South African Astronomical Observatory. The major telescopes were placed on a hill near Sutherland (pop. 2000) in the Karoo region of the northern Cape. Also in the 70's' the South African astronomy effort changed to a focus on the physics underlying stars and galaxies.

That focus becomes more pronounced with the proposed SALT. It will be an optical and infrared telescope modeled on the Hobby-Eberly telescope of the McDonald Observatory in Texas. SALT will conduct surveys in the spectroscopy of stellar objects. As it is on the drawing boards, it will be a match for the largest telescope in the world. It is expected that SALT will be completed in 4 to 5 years.

The length of time needed to complete SALT was the amount of time John Herschel devoted to observing the Southern sky from the favorable darkness of the Cape region. He came early on in the tradition of astronomical excellence. He was at the Cape from 1834-1838 with two telescopes. His larger one was a "sesquipedalian" of 18 inches in diameter. SALT is 11 yards in effective aperture. He was based at Feldhausen, SE of Capetown.

During his four years at the Cape, he determined the location of over 1700 non-stellar objects, many double stars were found, and many of the mysterious "nebulae", star systems or not, were observed. Halley's comet came round in 1835. Herschel observed the comet amidst the studies he was undertaking of the Magellanic Clouds and of sunspots.

He erected his large telescope on what are now the grounds of Grove Primary School. An obelisk, built in 1841, marks the spot where his telescope stood. This obelisk features a tribute to Herschel. It reads, in part, "contributed as largely by his benevolent exertions to the cause of education and humanity as by his eminent talents to the discovery of scientific truth".

In the present day, both a concern for education and scientific truth fuel the construction and use of SALT. Professor of Physics Hartmut Winkler at Vista University, Soweto campus, is located in Johannesburg. Hundreds of miles from him, SALT will join the other major SA telescopes on the hill.

In a recent email correspondence with Prof. Winkler, I asked him if he regarded astronomy as an easy way into science. He replied that astronomy is not always an easy subject, but that it is fascinating to the public and could be "a useful tool for drawing young people into the Sciences".

South African children have been cited as placing last in mathematics and science in a global comparison. Prof. Winkler was asked by me how this could be so. His reply was succinct - apartheid education. " Black South Africans were for too long actively discouraged form studying subjects such as Mathematics and Science".

SALT offers a hope of a scientific revival among the general population of South Africa. It cannot be a huge locus for tourism or single-handedly improve the fortunes of the country. Prof. Winkler, though, believes SALT will mainly be a much-needed stimulant for arousing interest in science, "which in turn we hope will boost technological development, and hence benefit the broader economy".

John Herschel had no such extra burden riding on his telescope. What would he make of SALT and its educative and economic function? Can SALT produce "benevolent exertions" in the cause of education and humanity in South Africa?










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