The MeerKAT array, currently taking shape in South Africa's Karoo region. Image: http://www.ska.ac.za
If Neil Armstrong’s “One step for man, one giant leap for mankind” defined exploration — and the US’ role in the world — in the 20th century, the Square Kilometre Array Telescope (SKA) will provide the platform for exploration in the 21st century.
If the space programme contributed to the USA’s technological leadership, imagine what the SKA could do for South Africa. South Africa’s bid to host the €1.5 billion (R18 billion) project is due to be adjudicated upon this month.
The SKA will be a virtual time machine, enabling scientists to explore the origins of galaxies, stars and planets. And South Africans are at the heart of its development.
South Africa, with eight other African countries, is competing against Australia & New Zealand to host an instrument 50-100 times more sensitive and 10,000 times faster than any radio imaging telescope yet built.
South Africa, allied with eight other African countries, is competing against Australia & New Zealand to host an instrument 50-100 times more sensitive and 10,000 times faster than any radio imaging telescope yet built.
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).
If South Africa wins the SKA bid, the core of this giant telescope will be constructed in the Karoo near 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.
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.
South Africa is no newcomer to major league astronomy. The Northern Cape is already home to one of the world’s largest telescopes, the Southern African Large Telescope or SALT.
South Africa also works closely with neighbour Nambia on the HESS gamma ray telescope, and is currently building an 80-dish precursor instrument for the SKA, the Karoo Array Telescope (also known as the MeerKAT).
Regardless of whether South Africa wins the SKA bid, the MeerKAT will be a powerful scientific instrument in its own right, comprising 80 dishes each 13.5-metres in diameter. It is being built adjacent to the site proposed for the SKA, in a radio astronomy reserve near the small town of Carnarvon in the Northern Cape, where it is due to be commissioned in 2015.
An engineering test bed of seven dishes, called the KAT-7, is already complete.
In October 2010, the Council for Scientific and Industrial Research (CSIR) announced that it would be installing a R100-million ultra-high speed broadband link between the Northern Cape sites of both the Square Kilometre Array and the Southern African Large Telescope (SALT) and the SA National Research Network backbone in Cape Town.
The ultra-high speed link will enable local and international researchers to process data from SALT and the KAT-7/MeerKAT in near real time, and significantly boost South Africa’s bid to host the SKA.
