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Cape Town - Astronomers in South Africa are part of a cohort of experts who are trying to build the most ambitious model of the universe using the latest technology.
Even though it is not yet built, scientists in SA are playing a leading role in trying to understand how the Square Kilometre Array telescope will be used to map the entire universe.
The SKA, so named because the project's surface area will encompass 1km2, will be built in Australia and SA and will give astronomers an unprecedented look at the early universe from as far back as 14 billion years ago.
But researchers will have to surmount a number of challengers at the limit of modern technology to accomplish what will likely be the most expansive survey of the universe.
"Researchers here have devised a means of using the world's largest telescope in new ways that will help shape the future of cosmology," said Roy Maartens, chair of the Cosmology Working Group and SKA SKA Research Professor at the University of the Western Cape.
Data demands
Beyond the engineering challenges of building an instrument in the arid Karoo outside Carnarvon in the Northern Cape Province, where the instruments have to withstand winds in excess of 144km/h, experts have to develop data management technologies.
The SKA precursor instrument the MeerKAT (Karoo Array Telescope) will consist of 64 linked radio telescopes, far lower than the SKA at around 3 000.
The MeerKAT will process around 343 000GB of data per day (one DVD per second), while the SKA will generate more data per day than the entire internet when it comes online in 2024.
This data will come mainly from processing information from radio signals generated by stars and galaxies, but the SKA team has proposed an even more demanding task to map the universe.
"The survey we are proposing will measure the emitted radiation from all the hydrogen atoms spread across the Universe without actually detecting galaxies. This will make it easier to survey all of the sky across cosmic times, allowing the phase 1 of the SKA to become an extremely competitive cosmology machine," said Professor Mario Santos, also a Research Professor at UWC.
"By making these huge, 3D maps of the universe we will be able to test the limits of General Relativity and maybe find some signature of new physics on these large scales which can shed light on the true nature of dark energy. Moreover, we can also look for imprints of what happened at the very beginning of the universe," he added.
Previous universe mapping utilised optical telescopes, but the SKA programme will be 50 times bigger and take about two years to complete.
"It will be like making a movie of the universe from a young age, when it was only about two billion years old, until today when it is about 14 billion years old. The movie will be low resolution but enough to test the fundamentals of cosmology," said Maartens.
Eleven countries have signed up to develop and fund the SKA which is expected to cost around €1.5bn.
Watch how MeerKAT engineers will control the instrument situated in the Northern Cape province from Cape Town.
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