SARAO

About the South African Radio Astronomy Observatory (SARAO)

The South African Radio Astronomy Observatory (SARAO), a facility of the National Research Foundation, is responsible for managing all radio astronomy initiatives and facilities in South Africa, including the MeerKAT Radio Telescope in the Karoo, and the Geodesy and VLBI activities at the HartRAO facility. SARAO also coordinates the African Very Long Baseline Interferometry Network (AVN) for the eight SKA partner countries in Africa, as well as South Africa’s contribution to the infrastructure and engineering planning for the Square Kilometre Array Radio Telescope.

To maximise the return on South Africa’s investment in radio astronomy, SARAO is managing programmes to create capacity in radio astronomy science and engineering research, and the technical capacity required to support site operations. The scale of the Square Kilometre Array (SKA) represents a huge leap forward in both engineering and research & development towards building and delivering a radio telescope, and will deliver a correspondingly transformational increase in science capability when operational.

Deploying thousands of radio telescopes, in three unique configurations, it will enable astronomers to monitor the sky in unprecedented detail and survey the entire sky thousands of times faster than any system currently in existence.

The SKA telescope will be co-located in Africa and in Australia. It will have an unprecedented scope in observations, exceeding the image resolution quality of the Hubble Space Telescope by a factor of 50 times, whilst also having the ability to image huge areas of sky in parallel. With a range of other large telescopes in the optical and infrared being built and launched into space over the coming decades, the SKA will perfectly augment, complement and lead the way in scientific discovery.

South Africa has already demonstrated its excellent science and engineering skills by designing and building the MeerKAT telescope – as a pathfinder to the SKA. The first seven dishes, KAT-7, are complete and have already produced its first pictures. MeerKAT is attracting great interest internationally – more than 500 international astronomers and 58 from Africa submitted proposals to do science with MeerKAT once it is complete.

The technology being developed for MeerKAT is cutting-edge and the project is creating a large group of young scientists and engineers with world-class expertise in the technologies which will be crucial in the next 10 – 20 years, such as very fast computing, very fast data transport, large networks of sensors, software radios and imaging algorithms.

Construction of the SKA telescopes

Construction of the SKA telescopes will take eight years (including 18 months contingency), having begun in July 2021 following approval by the SKAO Council. The telescopes will be delivered in phases, within an ambitious timeline as detailed in the table below.

The first major milestone, known as Array Assembly 0.5, is due to be reached in early 2024 with the completion of six SKA-Low stations and four SKA-Mid dishes. A further four Array Assembly milestones will see construction progress rapidly on both sites, with the completion of Array Assembly 4 - two full arrays - expected around 2028.

The commissioning process, which tests that components work together as a system, will take place as we progress through each Array Assembly stage. Science verification will also begin while the telescopes are still under construction, carrying out end-to-end tests of the system based on proposals for astronomical observations from the SKAO user community.

Commissioning and science verification ensure that the telescopes meet users' needs; carrying them out as each Array Assembly is constructed means any required adjustments can be made as early as possible in the process, minimising the risks as much as possible.

Following the completion of Array Assembly 4, expected in 2027 for both telescopes, a final Operations Readiness Review will take place. The formal end of construction is scheduled for July 2029.