KAT-7 observation boost for SKA
2012-03-15 16:13
Cape Town - South Africa has demonstrated the engineering of the Karoo Array Telescope has resulted in a capable instrument as the country makes the final push to host the Square Kilometre Telescope (SKA) in the Northern Cape province.
Known as the KAT-7, the seven dish array was able to detect radio emission from a nearby galaxy called NGC 3109, which is about 4.3 million light years away from Earth, in the constellation Hydra.
Astronomers were able to detect the radio emission from the neutral hydrogen gas in the galaxy as well as the direction it is moving.
"These exciting results achieved by KAT-7 have given us confidence that we know how to build a cutting-edge radio telescope in Africa to answer some of the fundamental questions in radio astronomy", said Dr Bernie Fanaroff, director of SKA South Africa.
SA and Australia are bidding to host the massive SKA, which will consist of more than 3 000 linked radio telescopes and the KAT-7 was built as an engineering test-bed for the project.
MeerKAT
Even if SA doesn't win the right to host the SKA, the ministry of science and technology has committed to build the MeerKAT instrument which will consist of 64 dishes.
"MeerKAT gets built, whether we win the SKA or not. If we win the SKA, things will change and we will have to re-plan a bit, but what we did was to align MeerKAT pretty close to the mainstream SKA thinking so that we'll be in a position to expand MeerKAT into an SKA Phase 1," MeerKAT project manager Willem Esterhuyse told News24.
Neutral hydrogen is important for the astronomers to understand the distances of galaxies from Earth using the Doppler effect. Where galaxies are moving away from us, the frequency shifts down.
One of the first projects slated for the MeerKAT after its expected completion in 2016 will study neutral hydrogen in great detail.
"We want to go back to about half the age of the universe - about six to eight billion years - and we'll be able to measure the gas from the most distant galaxies," astronomer Dr Sarah Blyth told News24 in late 2011.
Blythe will, with Dr Andrew Baker of Rutgers University and Dr Benne Holwerda of the European Space Agency, lead a team of 56 to study the prevalence of neutral hydrogen in the universe. Their research hopes to explain the decline in star formation in galaxies.
"Observations of the neutral hydrogen content of galaxies also help to form a picture of how galaxies have evolved over cosmic time and show how our own galaxy, the spiral galaxy called the Milky Way, has developed," Fanaroff said.
Recently a scientific review panel has recommended SA as a host country for the SKA, but the final decision is expected in April and the project is expected to cost about €1.5bn.
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