The Square Kilometre Array (SKA) project being built 80km from Carnarvon in the Northern Cape is pushing South Africa closer to the forefront of exciting astronomical discoveries from the universe.
SKA SA is part of a global project to build the world’s largest ever radio telescope which, on completion, will have a total collecting area of about one million square metres with a centralised computer that has the capacity of about 100 million PCs to process data.
With its headquarters at the Jodrell Bank Observatory in the UK, the SKA has grown into an international project bringing the world’s foremost scientists, engineers and decision makers from its core membership in ten countries, including South Africa and Australia. Sites in these two countries were chosen in 2012, with Australia’s Murchison region hosting the low-frequency arrays, while Carnarvon is the site of the mid-frequency arrays.
The SKA is expected to push boundaries beyond known limits of human engineering, scientific endeavours and data capturing abilities that will search for life outside our known universe and look for answers to important scientific questions such as the origin of cosmic magnetism, energy and black holes.
The Northern Cape is already host to the KAT7 telescope array, an essential testing site for the MeerKAT telescope array (formerly KAT - the Karoo Array Telescope), a 64-dish system that will be a forerunner to the full SKA telescope system.
In May, while astronomers from around the world met in Stellenbosch to discuss the scientific potential of MeerKAT, the telescope produced its first image using just four of the 64 dishes, with radio waves from galaxies in the distant universe that have never been viewed before.
“This holds enormous significance for us,” explains SKA SA associate director for science and engineering, Professor Justin Jonas. “This image and all that goes with it adds to our confidence that this very complex project will be the success that we have been planning for over ten years.”
SKA South Africa’s principal scientist, Dr Fernando Camilo explains the image captured by MeerKAT is less than 0.01% of the entire celestial sphere.
“Considering that we detected over 50 galaxies in such a small patch of sky, using only four dishes, imagine the discoveries that will be made when we survey the entire South African sky with the full 64-dish MeerKAT.”
South Africa a major role-player in scientific and Big Data industries
SKA SA director, Dr Bernie Fanaroff is passionate about the SKA and his role in the project. “We want to prove to the world that South Africa is a major role-player in science, technology and the Big Data industry. If you have a vision, you need to convince people of that vision, and continue to be extremely stubborn and focused on it.”
South Africa’s long history of astronomical research, along with Africa’s renewed position as a centre of scientific excellence was key to securing the South African bid to co-host SKA with Australia.
“Not only will there be exciting discoveries coming out of the SKA, but there will also be challenges in how to cope with the enormous amount of raw data that this construction will produce.”
Fanaroff explains that the SKA will increase understanding of the evolution of the universe, its expansion and formation of plants amongst other things, such as how dark energy and dark matter occurs. “But the biggest discoveries that radio telescopes have become famous for are the unpredictable discoveries, and the design of the SKA lends itself to that.”
He says that the sensitivity of the SKA telescope is futuristic and goes way beyond what has been used before. “It is far better than anything we’ve had before and it will open up entirely new avenues and covers a far greater wavelength spectrum.”
SKA working with partners to process huge volumes of science data
Due to the nature of the SKA there will be a huge amount of scientific data that will need to be processed and Fanaroff says that during the first phase, the project has been broken down into small packages, which different consortiums in the SKA member countries will focus on.
“A large consortium is working on processing science data, which comes after the initial computing stage. It takes a lot of work to process the huge volume of data coming through without expending a lot of energy.
“Then there is a new challenge as to what algorithms can be used to take the data that’s been processed up to a certain point, calibrate it, and make images from it. Although we know how to make images and calibrate data in smaller fields of view, we are now having to design new science in order to calibrate and see everything with great fidelity over the entire field of view,” explains Fanaroff, adding that there is already a strong South African consortium working on third-generation calibration.
The big question, says Fanaroff is how to distribute, store and analyse huge amounts of data around the world as the volume is too great for ordinary computers and laptops.
“There are a lot of people who work in the field of Big Data, and countries like the UK are investing heavily in the SKA, because they want to develop Big Data capacity. The possibilities are exciting not just for astronomy but for social and economic development as well.”
Challenge of radio frequency interference could impact aviation and cellphones
There will be several challenges for the SKA as the giant radio telescope will operate over a large range of frequencies, which promise to be strong enough to detect radio waves millions of light years away from Earth.
A major challenge is that the radio telescope needs to be protected from radio frequency interference, which has caused an impasse between SKA SA and the local aviation authorities over restriction of some radio frequencies in the Karoo. An area of around 131 500 hectares that surrounds the telescope’s 176-dish core needs to be free from radio frequency interference.
In order for the telescope to function at such a high level of sensitivity, it will need to be protected from radio frequency interference such as that of two-way communication between pilots and air traffic controllers in the area.
The Civil Aviation Authority (CAA) says there are fears that the restriction on using the frequency spectrum to communicate with pilots could see aircraft on the Johannesburg – Cape Town route being rerouted over the Atlantic Ocean, over Upington or even via Port-Elizabeth.
A draft Astronomy Geographic Advantage (AGA) Act has been published for public comment, regarding the proposed protection of the SKA from radio interference. The frequency spectrum that is in question is from 100MHz to 25.5GHz.
SKA SA project director Dr Rob Adam says that the draft regulations specifically recognise the importance of safety-of-life services, like those used in aviation and other services using these frequencies. “We want to provide for exemptions of these services from the strictest of the SKA protection requirements and that the net result of these draft regulations is that services such as commercial air traffic would not be affected.”
However, Adam reiterates that low-level flights directly over the SKA could damage the sensitive equipment and that SKA SA will continue to involve CAA in discussions to safeguard against this happening. Cellphone signals could also be affected as the law and regulations that have to be followed will impact the lives of people living in astronomy advantage areas (AAA).
“The AAAs that have been declared to date include the Northern Cape, but exclude the Sol Plaatje Municipality, the Karoo Core AAA and the Karoo Central AAAs, as published in the Government Gazette on 12 March 2014,” explains Lorenzo Raynard, SKA SA communication manager. He adds that cellphone signals will only be affected in the core area of the telescope and that people living in the towns surrounding the core area such as Williston, Vanwyksvlei, Brandvlei and Carnarvon will not be affected by any restrictions on cellphone coverage.
Communities benefiting from training
Setting up a scientific project using high-end technology and research in a remote area such as that of the Northern Cape could be seen as a challenge due to the extreme lack of skilled workers needed.
Fanaroff explains that the rural area around the SKA is extremely poor, with an unemployment rate of 85%. “This is exacerbated by the lack of skills in the community. It is not an area that has produced many qualified science and maths teachers, so we are working with schools, providing them with computer labs and helping to teach the learners maths, science and relevant languages.
He adds that 40 bursaries have been given to promising learners who are being trained as artisans or technicians. “We have already employed quite a few and it has had a positive effect on the community as it is the first time there is a clear example of what you can do if you do well at school. It’s really important that we make these efforts because you cannot exclude and antagonise the community of which you will be a part of for over 50 years.”
Young women empowered to enter into international space race
Interest in the SKA has also increased curiosity in the international space race and knowing this the South African Meta Economic Development Organisation (Medo), launched its space programme for young women recently, with the aim of sparking a passion in them for applied sciences by involving them in building and launching a satellite into orbit. It is a three-phased programme that empowers young women to build and launch small CricketSat satellites, as well as designing and implementing payloads for the satellites.
The launch of Medo’s first satellite is expected to take place later this year, making it the first private company in Africa to build a satellite and send it into orbit. “I feel inspired because I never thought that a girl from a township could be doing these big and amazing things, learning from world-renowned astronomers,” says Medo graduate Nwabisa Sithole.
Government and business support building proficiency and skills
Government has also given the SKA its support as it sees it as a flagship programme for the country. It has also received backing from countries involved in the fields of astronomy, science and technology.
Another flagship programme in South Africa is Big Data Africa, which is developing wider proficiencies in Big Data and data science.
Fanaroff says IBM has started a research lab in Johannesburg for machine learning, while the Inter-University Institute for Data Intensive Astronomy (IDIA) has been established in partnership with three South African universities doing work beyond astronomy in areas such as bioinformatics.
“We are working with the IDIA, our Centre for High Performance Computing on the African Research Cloud, with partners in various countries, including the Netherlands, France and the UK.”
Fanaroff points out that the SKA and the African Very Long Baseline Interferometry Network is the first focus area, but once the infrastructure is complete and the necessary staff trained to operate and maintain the facility it will be integrated into the European research cloud.
“This project will be a very powerful tool for astronomers and researchers in Africa, but will also open up a much wider field of data science competency, that can be used in business, government, and into improved service delivery.”
As outgoing director, Fanaroff comments that he has been very encouraged and excited to see the way the SKA has motived people into the science and engineering fields. “We have become a spectacular team, among the best in the world in the field of engineering and science, the likes of which people never thought we would be capable of.”