Q&A: SKA’s Associate Director for Science and Engineering
On 25 May 2012 the Members of the SKA Organisation announced that the SKA telescope would be split over Africa and Australia, with a major share of the telescope destined to be built in South Africa.
Prof Justin Jonas, Associate Director: Science and Engineering at SKA South Africa answers some FAQs regarding the outcome of the SKA site bid and the future of the SKA.
How important is the SKA site bid outcome for South Africa? What does it mean for the country?
This is a very significant moment for South Africa, and Africa as a whole. It is also an important milestone in the international SKA project – the overall winner here is global science. For South Africa and our African partner countries this represents a new era, where Africa is seen as a science destination and takes its place as an equal peer in global science.
What do you think differentiated South Africa’s bid from Australia?
The higher elevation of the South African site (1000 m) is an advantage for the mid-frequency telescope, hence the allocation of this segment of the SKA to South Africa. The SKA Site Advisory Committee (SSAC) report can be found at www.skatelescope.org
Did the Astronomy Geographic Advantage (AGA) play a critical role is South Africa’s successful bid for the SKA?
The AGA Act provides protection for all astronomy activities within designated areas within the Northern Cape Province. It provides long-term protection of the radio spectrum in these areas, which is critical for the SKA to achieve its scientific goals. The AGA Act was an important factor in South African SKA proposal.
How will the SKA be split between Africa and Australia? Is this feasible, given the distance between the two continents?
The SKA consists of two quite distinct components: one working at low frequencies and one working at mid frequencies. The two components use very different antenna technologies and operate independently. For this reason it is quite easy to separate the SKA into these two components, and build them on separate sites. Even if the SKA had been allocated to one country the two components would have been separated by quite a large distance.
What are the potential advantages and disadvantages of a dual site?
Firstly, there is no detriment to the science, and for Phase 1 there may even be advantages because of the use of existing investments at both sites. Management will be slightly more complicated, but the SKA Organisation is already distributed across many countries. The implementation cost will inevitably be higher because of some duplication of infrastructure and differential construction and operations costs between the countries, but this may be offset by greater participation and hence Membership contributions.
How will be components of the SKA be split across both continents?
SKA Phase 1 (about 10% of the total SKA)
|South Africa’s precursor array – the 64-dish MeerKAT telescope – will be integrated into
Phase 1. An additional 190 mid-frequency dish-shaped antennas, each about 15 m high will be built.
|Australia’s 36-dish SKA Pathfinder (ASKAP) will be integrated into Phase 1. An additional 60 mid-frequency dish-shaped antennas, each about 15 m high, will be built, as well as a large number of small, low-frequency antennas – each about 1,5 m high.|
SKA Phase 2
South Africa & African partners
|A total of about three thousand mid-frequency dishes, with the highest concentration in the Northern Cape, South Africa, but some dishes in Namibia, Botswana, Zambia, Mozambique, Kenya, Ghana, Madagascar and Mauritius. In addition, a large number of flat mid-frequency antennas, each about 60 m in diameter (number to be determined).||Up to 10 times more of the low-frequency antennas – each about 1,5 m high.|
What about the cost? How much will each contribute? Will the cost of building the telescope increase due to the split?
Capital and running costs for the SKA will come from contributions from all of the Members of the SKA Organisation. The split in costs will depend on the number of Members, currently eight, that join the organisation. In the SKA Phase 1 era they may be a saving on costs because the split site scenario allows the use of existing infrastructure on both sites. In the Phase 2 era there will be a need to build duplicate infrastructure, but the cost of this has not yet been determined with any accuracy. The increase is expected to be a relatively small fraction of the total cost.
What are your plans for the SKA site in South Africa? What will it include?
Currently the South African SKA site is being developed for the MeerKAT precursor telescope. The infrastructure that is already developed, and will be developed over the next few years, will be used for both the MeerKAT and SKA Phase 1. This infrastructure includes electric power from the national grid, data connections to major academic networks, and buildings to support the construction and operation of MeerKAT and the SKA.
What role do the international partners have in the project – how do they contribute? What kind of support are you looking for from the international community?
The SKA is a global project and depends fundamentally on support from all of the Members of the SKA Organisation. The SKA will not only consist of the antennas to the two sites, but very importantly consists of a distributed network of staff, institutions, data networks and computing facilities located in the Member countries. Capital and operations costs will be covered by contributions from the Members.
Who is now going to lead the SKA project?
The SKA is a global project, and it will be managed by the SKA Organisation which is a company registered in the UK. All of the Members of the Organisation will participate in the management, development and construction.
What kind of impact will the SKA have on the development of science and technology in Africa?
The SKA has already had an impact through the MeerKAT project and the human capital development project that is managed by the SKA South Africa project office. The MeerKAT has provided African academia and industry with challenges that have improved their competitiveness, and the human capital programme has increased the numbers of students taking degrees up to the PhD level in physics, mathematics and engineering. Being much larger, the SKA will take this to the next level.
Does the SKA project create any specific opportunities for increased collaboration with the other BRICS countries?
China is already a Member of the SKA organisation, and India has a long involvement in the SKA and will likely become a Member in the future. Russia and Brazil have both shown interest in the SKA, and may join at a later date. We are currently working very closely with our Indian colleagues of high performance data process and computing systems, and have engaged with Chinese industry with regard to the construction of dishes.
What makes the SKA different from other radio telescopes?
The SKA will be about 50 times more sensitive than any other existing radio telescope. It is not fundamentally different from existing instruments, but it will make use of the most advanced technologies available to provide the most favourable cost/performance ratio.