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The Square Kilometre Array (SKA) will be a mega radio telescope, about 100 times more sensitive than the biggest
existing radio telescope. The SKA will consist of approximately 4 000 dish-shaped antennae and other hybrid receiving
technologies. It will have a core of several hundred antennae and outlying stations of 30 - 40 antennae spiralling out of
the core. These stations will be spread over a vast area - up to 3 000 km. The combined collecting area of all these
antennae will add up to one square kilometre (= one million square metres).
This mega telescope will be powerful and sensitive enough to observe radio signals from the immediate aftermath of
the Big Bang. It will search for Earth-like planets and potential life elsewhere in the universe, test theories of gravity and
examine the mystery of dark energy. A prime objective of the SKA is to probe the so-called "dark ages", when the early
universe was in a gaseous form before stars and galaxies were formed. Scientists are optimistic that the SKA will allow
many new discoveries about how the universe was formed and what it is made of.
The SKA will detect electromagnetic radiation (radio waves) and cosmic rays emitted by extremely distant celestial
objects (such as stars and galaxies). Because electromagnetic radiation travels at a fixed speed of about 300 000 km
per second, very distant objects are observed as they were in the distant past. This will allow astronomers to "look back
in time" to observe the early stages of the evolution of the universe.
The SKA must be built in a remote area, as far away as possible from man-made radio interference which is caused by
sources such as cellular masts, radio broadcasts and air traffic navigation signals. Both South Africa and Australia have
suitably remote, radio quiet areas for hosting the SKA. The international radio astronomy community must decide on the
optimal site by 2011. They will base their decision on detailed studies of the advantages and disadvantages of both
sites, in terms of scientific requirements and comparative costs.
If South Africa wins the SKA bid, the core of this giant telescope will be constructed in the Karoo region of the Northern
Cape Province near to the towns of Carnarvon and Williston, linked to a computing facility in Cape Town. However, the
SKA is so huge that outlying stations will be spread over several African countries, including Namibia, Botswana,
Mozambique, Zambia, Mauritius, Madagascar, Kenya and Ghana.
SKA is a €1.5 billion project, with operating costs of about €100 million a year. At least 24 organisations from 12 countries,
including Australia, Canada, India, China, France, Germany, Italy, Portugal, Spain, South Africa, Sweden, the
Netherlands, the UK and the USA, are involved. Europe is expected to fund 40% of the project, with a comparable
amount from the USA. The balance will be funded by the other countries involved in the project.
The SKA will be built in phases. It is expected that construction will start in 2012, with significant collecting area in place
by 2015 and the full array completed by 2021. South Africa and Australia are building "pathfinder" telescopes to
develop and test the technology and science for the SKA. These are both due for completion in 2012 and will be
extremely powerful, new generation radio telescopes.
Southern Africa has become a hub of activities in the field of astronomy and related technologies. We have the
infrastructure and expertise in place to make the SKA project a success. Winning the SKA bid will be a major step
forward for the government's Astronomy Geographical Advantage Programme (AGAP), building on the Southern
African Large Telescope (SALT), the Hartebeesthoek Radio Astronomy Observatory (HartRAO) and the HESS gamma
ray telescope in Namibia. The Karoo Array Telescope (known as MeerKAT) is being built on the site proposed for the
SKA. South Africa's new Astronomy Geographic Advantage Act ensures the future of radio astronomy in South Africa by
protecting an area of about 12.5 million hectares around the proposed SKA core area against future radio frequency
interference.
The SKA project will have substantial long term benefits for South Africa and Africa, corroborating our position as a hub
for technological investment, creating local job opportunities, investment in human capital and directly increasing the
uptake of science amongst young people.
The Northern Cape is an ideal location for hosting the SKA. Because the area is remote and has very few people, it is
radio quiet (in other words, it has very low levels of radio frequency interference). In addition to its ideal geographical
location, sky coverage and topography, the basic infrastructure of roads, electricity and communication are in place.
The land, labour and services required by the project are available and affordable and the Karoo is a safe and stable
area with no conflicting economic activities. Finally, South Africa offers the astronomical "richness" of the southern skies
and a strong tradition of astronomy.
South Africa is building a premier mid-frequency radio telescope, The Karoo Array Telescope (known as MeerKAT), at
the site proposed for the SKA. MeerKAT serves as a "pathfinder" for the cutting-edge technologies of the SKA. Phase one
of MeerKAT - the construction of the first seven dishes (called KAT-7) - is under way on the site in the Karoo. The team
plans to have the first KAT-7 dish on site by mid April 2009 and all seven dishes on site by December 2009. MeerKAT will
eventually consist of up to 80 dishes, each 12 m in diameter. The telescope should be fully operational by 2012.
One of the major reasons for the support of the South African SKA project by government is that it can attract young
people into science and engineering. The SKA South Africa Project, including the building of MeerKAT, is one of the
biggest science and engineering projects currently in progress in South Africa and presents a variety of very exciting
technological and scientific challenges and opportunities. It requires skills across a wide range of engineering
disciplines, such as digital signal processing, radio frequency engineering, antenna design and software development.
The South African SKA Project is supported by a targeted "Youth into Science and Engineering Programme". The
programme offers comprehensive bursaries to students in engineering, mathematics, physics and astronomy at
undergraduate and postgraduate level. Students who receive bursaries also benefit from regular workshops and
student conferences where they interact with the world's leading astronomers. To date more than 80 postgraduate
students from South Africa and the rest of the African continent and 36 undergraduate students are studying or have
studied with SKA bursaries and are on their way to being a part of South Africa's exciting future in radio astronomy.
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