SKA is serious business for SA
Space exploration is by many regarded as a waste of money and a futile use of human resources. If that is the case, why do governments persist in making funding available to fund these activities? NASA, with its proven record of the huge contribution the space programme has made and is making to mankind, is still subjected to verbal abuse by certain sectors of the population.
In South Africa the Department of Science and Technology was created to take South Africa to the enlightened world of science where science is practised for its outcome and contributions to South Africans. This objective is concisely spelt out in the Department’s vision: "To develop, coordinate and manage a national system of innovation that will bring about maximum human capital, sustainable economic growth and improved quality of life."
History has shown that for any scientific discipline to remain active and productive, the power of its instrumentation must grow exponentially with time. Without this growth the discipline tends to stagnate and new discoveries are not made. It is with this vision in mind that South Africa became involved in a bid to host the Square Kilometre Array project (SKA).
Most of the radio telescopes in use today were built 10 to 30 years ago. For radio astronomy to progress, a new telescope with one hundred times the collecting surface of existing telescopes will be needed in about ten years time.
The SKA was conceived as a new international project to meet the future needs of radio astronomers. One of the prime objectives of the SKA is to probe the so-called "Dark Ages", when the early universe was in a gaseous form before the formation of stars and galaxies. At present astronomers do not have the necessary tools to observe radiation from this period of the universe, which extends from about 300 000 years till 1 billion years after the Big Bang.
The SKA will provide data for a whole range of astronomical investigations, and it will complement other planned instruments in the optical, infrared and millimetre wavebands. It will provide sharp radio images of all categories of astronomical objects, investigate the nature of the enigmatic gamma-ray burst sources, detect the gravitational waves predicted by Einstein’s theory of general relativity by using radio pulsars as cosmic clocks, detect extra-solar planets, and may even detect signals transmitted by intelligent extraterrestrial civilisations (SETIs).
From the day that the international scientific community mooted the SKA idea, there has been fierce competition by countries bidding to host the project. Ultimately the race narrowed down to South Africa and Australia
The SKA is serious business for SA
Scientists and engineers from around the world met in Australia April this year to kick off the preparatory phase. The SKA has been identified by the European Strategy Forum for Research Infrastructures (ESFRI) in its 2006 Roadmap for research infrastructures of pan-European relevance. The corresponding preparatory phase project, called PrepSKA, will now pave the way for the SKA, with a three-year programme to draw together international efforts from around the world to finalise a detailed, costed technical design and to develop the governance and legal framework for the project. PrepSKA will also conduct additional studies of the short-listed sites in Australia and South Africa.
The PrepSKA collaboration initially involves 24 organisations from 12 countries, including: Australia, Canada, France, Germany, Italy, Portugal, Spain, South Africa, Sweden, the Netherlands, the UK and the USA.
PrepSKA is a €22-million programme, with €5,5-million from the European Union’s Seventh Framework Programme (FP7) and further funding provided by the participating countries. PrepSKA runs until 2011.
Once PrepSKA is complete, there should be an agreed design for the largest array of radio antennas ever built, allowing interested countries to decide on their involvement with the final SKA project.
Building work is due to start in 2013, subject to successful funding proposals. The SKA will be constructed in a phased manner over a seven year period. Operations should start in 2015 once a significant portion of the array has been commissioned. The array will be constructed of ~4000 antennas spread with a total collecting area of a square kilometre. The antennas will be distributed in ~200 ‘stations’ spread over ~3000 km.
If South Africa wins the bid to site the SKA, the core of the telescope (consisting of approximately 3000 antennas) will be located in the Karoo region of the Northern Cape Province, approximately 95 km north-west of Carnarvon. The other antenna stations will be distributed throughout South Africa and a number of African countries.
South Africa takes the lead with the meerkat SKA pathfinder project
In 2004 South Africa began on the design, development and construction of the MeerKAT, an SKA pathfinder array of telescopes. The name Meerkat was derived from the Karroo Array Telescope and because the initial project involves the building of seven telescopes, the Afrikaans word "meer" meaning more was added to the KAT acronym.
MeerKAT will consist of up to 80 x 12 m antennas. It will be located at the site selected for the SKA and is due for completion and commissioning by the end of 2012. The development of the MeerKAT is taking place in phases to optimise the design of the telescope and reduce the risk at each stage. It is designed to maximise the scientific output. A 15 m prototype antenna has been constructed at the Hartebeesthoek Radio Astronomy Observatory in Gauteng from composite materials. This is the first large antenna in the world to be manufactured from composites. Tests on this antenna have improved the design and an optimised
A 12 m antenna will be constructed for a seven dish array to be constructed in the Karoo by the end of 2009. The final phase will see the construction of the array of up to eighty dishes by 2012. The land for the site has been procured and road, power and communication infrastructure are near completion. Although in this respect South Africa is well ahead of Australia developments the decision which country will ultimately host the SKA is still some years off.
According to Dr. Adrian Tiplady, a prominent member of the SKA team responsible for Project Science and Radio Frequency Interference, a significant amount of technology, software, algorithms and RF designs developed for Meerkat will contribute to PrepSKA.
The SKA project supports a large number of students. "We currently have around 80 mostly from South Africa and a few students from our partner countries where if the SKA comes to us some aspects of the SKA will be built," said Dr. Tiplady.
"One of main benefits of the SKA bidding project is the large amount of high-end research that is carried out at our universities, building human capital with expertise that will not only support the development of astronomy capability in South Africa but will make a large number of highly skilled people available to a wide range of industries.
"A large number of students are at post graduate levels and study under a supervisor from their own university and a supervisor from another international institution which gives them great exposure to the world’s best resources. As part of this programme astronomy departments are being established at more universities. Traditionally only Rhodes University and the University of Cape Town offered astronomy as a field of study.
"The bottom line is that although we hope that the SKA comes to South Africa the benefits the country is deriving from current projects is huge in terms of human capital development. We have already seen appreciation of our expertise from universities in many of the participating countries . Their eagerness to involve us in their research and development programmes is another indication that we are doing the right thing," Dr. Tiplady said.
EngineerIT
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