Africa’s Giant Eye on the Sky

SALT Observatory, South Africa

SALT Observatory, South Africa (Kevin Crause)

The Southern African Large Telescope (SALT), situated and built in South Africa, is the largest single optical telescope in the southern hemisphere and amongst the largest in the world, with a hexagonal primary mirror array that is 11 metres in diameter.

SALT is funded by a consortium of international partners and hosted and operated by the South African Astronomical Observatory (SAAO). It is located in the Karoo semi-desert in South Africa, near the village of Sutherland. Not only is this one of the darkest astronomical sites in the world, but it is ideally located between the other large optical observatories of the southern hemisphere, in Chile and Australia, to allow continuous coverage for time-critical observations.

Its queue-scheduled mode of operation allows for rapid response — often within a day or two. This, together with the fact that the full range of instruments is available at all times, allows observers to quickly switch between targets, making it a powerful instrument for transient follow-up observations. This capability was demonstrated with the first multi-messenger event, GRW20170817, in which SALT was one of the first telescopes to obtain a spectrum.

This South African flagship project demonstrates that the frontiers of science are not exclusively reserved for the developed world. SALT provides a first-class and cost-effective facility for astronomical research in Africa. Strong ties have been established with researchers around the world that benefit local young scientists and engineers. One of SALT’s strategic objectives is human capital development, and already South Africa has seen substantial growth in its community of professional astronomers, thanks to this telescope and MeerKAT/Square Kilometre Array; there are now about 200 PhD astronomers at institutes around South Africa and many more students at other levels of study.

At our booth in the GA we offer information on specifics of the telescopes and instruments. The 2017 Annual Report shows what kind of science is typically done with SALT, and astronomers interested in observing with SALT can find out more about the procedure. Another small brochure introduces the SALT partners. Currently, the SALT consortium is seeking an additional 10%-level partner to support significant second-generation instrumentation development.

Anja SchroederANJA SCHROEDER is PR officer at SALT. Her main research topic is tracing large-scale structures behind the Galactic Plane using a multi-wavelength approach.


Mose MogotsiMOSE MOGOTSI is a postdoctoral researcher at SAAO, working on multi-wavelength studies of star formation and gas and stellar dynamics in nearby galaxies.