Durban - The first image from MeerKAT shows that the telescope “will be a remarkable discovery machine”, the project’s chief scientist, Dr Fernando Camilo, says.
“The images tell us all that MeerKAT is the best telescope of its kind in the southern hemisphere, with only 16 dishes,” he told ministers, deputy ministers and visitors gathered at the site of the Square Kilometre Array (SKA) in the Northern Cape on Saturrday.
Science and Technology Minister Naledi Pandor inaugurated the first 16 dishes of the MeerKAT telescope - and unveiled its first image.
By the end of next year, the South African-designed and built telescope will comprise 64 dishes.
These giant two-storey dishes rise up out of the centre of the MeerKAT core area, standing incongruously against a backdrop of ocre sand and scrubland.
Others wait to be assembled, their white metal bowls ready to be hoisted on to pedestals.
“When the full 64-dish MeerKAT is available, it will be the best telescope of its kind in the world,” said Camilo, who left Columbia University, New York, to take up the post in April.
It was difficult to get to this stage as there was usually a need for trouble-shooting before a telescope could produce a high-quality image.
“(The image) tells us and the world that we have a working telescope in the Karoo,” Camilo said.
Although the R3 billion MeerKAT is owned and funded by South Africa, it will be incorporated into the SKA, which is to be the largest telescope in the world.
The SKA is an international project and will be hosted by Australia and South Africa, with satellite sites in eight African partner countries.
It will seek to answer some of humanity’s most enigmatic questions: Are we alone in the universe, what is dark matter, how do galaxies evolve, and what happened after the Big Bang?
From 2018, another 133 dishes will be added to MeerKAT to form part of the phase one of the SKA, the cost of which has been capped at R10bn.
In Australia, about 130 dipole antennas, which look like 2m Christmas trees made out of thick wire, will be constructed as part of this phase.
South Africa decided to build MeerKAT even before it was announced in 2012 that the SKA would be split between the two countries.
This was in part to showcase South Africa’s scientific and engineering capabilities and prove the country could build and host a radio telescope.
The intention was also to ensure it would have a legacy project in case the country lost the hosting bid.
“This is not just an unveiling,” Pandor said yesterday.
“We want to show the world the kind of research that the MeerKAT-16 makes possible... We were meant to reach this (quality of image) at 32 (dishes), not 16.”
It is difficult and expensive to engineer a radio telescope with a single big dish. This is why the MeerKAT - and ultimately the SKA - is an interferometer, which uses many smaller dishes acting as one giant telescope.
This means an interferometer can be brought into use in phases and the radio telescope can be used for scientific work before all phases have been completed.
Professor Justin Jonas, SKA South Africa’s chief technologist, said he was “amazed” at the quality of the image.
He added, however: “There are no accidents here. It’s been a coherent effort from the whole team and the National Research Foundation and the Department of Science and Technology... We hired the right people, had the right processes in place.
“Personally, I’m very, very excited. I’ve been wanting to build a radio telescope since I was a kid, and now we have. How many people get to do that? And it’s working!”
The released image was a picture of about 1 300 radio galaxies, of which only 70 had been imaged before, said Jonas, who attended the first international SKA meeting as South Africa’s ambassador.
Celestial objects, like stars and galaxies, emit radio waves, which cannot be seen with the naked eye.
Radio telescopes receive these fairly weak signals from the universe and turn them into maps and images of the universe.
The radio spectrum is substantially broader than that of visible light, which means scientists can “see” more with radio telescopes.
The “first light” image was taken in the L-band, which is a portion of the radio spectrum.
This band is of interest globally because it contains information about how galaxies and the universe evolve, among other things.
MeerKAT is expected to be twice as sensitive in this band as was initially anticipated. This means an experiment in this band could take a quarter of the time that has been allocated.
Pandor said there was more to South Africa’s astronomy investment than pure science: “Big science brings opportunity to South Africa and the African continent.
“The SKA brings opportunities to this area, opportunities they hadn’t hoped for.”
It was “not always easy to convince governments to support long-term projects and initiatives, especially in science… (where) there are often nuanced impacts that are not immediately visible”.
Pandor encouraged Economic Development Minister Ebrahim Patel, 11 deputy ministers and the other dignitaries present to be “ambassadors for science and the SKA”.
“Science and astronomy science can change lives, change communities, build human capital.
“Through science, in South Africa and Africa, we are able to advance development.”
* Wild was a guest of the Department of Science and Technology and SKA South Africa.
Sunday Tribune