of SARAO. “There was an idea to build a transformational radio telescope, which would take the field to a whole new level and which would be capable of making contributions not just in astronomy but basic physics as well.” In the early-2000s, this idea intersected with the South African government’s priorities. “In the post-apartheid boycott era, we were looking for ways to attract investment in South African science from the wealthier Northern Hemisphere countries,” says Dr. Adam. “Astronomy was one of the key areas we were looking at, because we have these empty expanses where there are relatively few people living and there is no light pollution or radio pollution. These are perfect sites for an observatory.” When human beings use telescopes to look beyond the Earth’s atmosphere into the wider universe, we use three parts of the electromagnetic spectrum to do so: The optical portion (including visible light), radio, and gamma rays. “We essentially have three windows on the heavens,” says Dr. Adam. “So South Africa systematically looked to get involved in projects in each of those areas. We have the South African Large Telescope (SALT), which is an optical telescope at Sutherland. Then there’s the High Energy Stereoscopic System (HESS) gamma ray telescope, which was erected in Namibia by a German-British-French-South African consortium. And finally there’s SKA, which is by far the largest of these projects. We spent a decade positioning ourselves for it, preparing our capabilities in construction, electronics, and astronomy.”
MEERKAT As part of South Africa’s preparations for SKA, the team worked on several smaller-scale radio telescope projects of progressively increasing ambition. In 2005, the Karoo Array Telescope (KAT) computing team conceived the Phased Experimental Demonstrator (PED), a six-element interferometric radio telescope which was funded by SKA South Africa and constructed at the South Africa Astronomical Observatory (SAAO) in Cape Town. This smaller-scale radio telescope allowed the team to test software and develop an understanding of radio interferometry. “After that, we built our first array, which was the KAT-7, and after that we began work on MeerKAT,” says Dr. Adam. “MeerKAT, which is a 64-antenna array, is a precursor to SKA, where we could test the technology, and it was agreed that if we won the bid, it would be integrated into SKA. We’re due to complete MeerKAT in March 2018, and it will be effective in the ensuing months. After that, we envisage SKA-1 construction will start in 2019, which will take around five years, and after that SKA-2, which will finish in the late 2020s.”
THE HYDROGEN EPOCH OF REIONISATION ARRAY IS CURRENTLY BEING BUILT AT LOSBERG IN THE KAROO AND WILL BE INSTRUMENTAL IN DETECTING THE DISTINCTIVE SIGNATURE THAT WOULD ALLOW ASTRONOMERS TO UNDERSTAND THE FORMATION AND EVOLUTION OF THE VERY FIRST LUMINOUS SOURCES: THE FIRST STARS AND GALAXIES IN THE UNIVERSE.
Kenya, Madagascar, Mauritius, Mozambique, Namibia, and Zambia. DECADES IN THE MAKING “The genesis of this project is in the radio astronomy community in the 1990s,” explains Dr. Rob Adam, Managing Director SUSTAINABLE BUSINESS MAGAZINE
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