25 Feb South African Telescopes to Follow-Up Rubin Observatory Alerts This Week
South African Telescopes to Follow-Up Rubin Observatory Alerts This Week
Cape Town, South Africa — 25 February 2026 — The Southern African Large Telescope (SALT) is about to begin observing selected astronomical alerts issued by the Vera C. Rubin Observatory, marking an important step in South Africa’s participation in a new era of time-domain astronomy [link to Rubin press release].
Rubin Observatory, based in Chile, is conducting one of the most ambitious sky surveys ever undertaken. Using its powerful 8.4-metre Simonyi Survey Telescope, it repeatedly scans the southern sky, detecting transient and variable events — from exploding stars (supernovae) to flaring black holes and potentially hazardous near-Earth asteroids. These discoveries are rapidly distributed worldwide as “alerts,” enabling partner facilities to carry out detailed follow-up observations.
SALT, located at the National Research Foundation’s South African Astronomical Observatory (NRF-SAAO) at Sutherland in the Northern Cape, is exceptionally well-positioned to respond to these alerts. As the largest single optical telescope in the southern hemisphere, with an 11-metre segmented primary mirror, SALT combines light-gathering power with state-of-the-art spectroscopic instruments. This makes it particularly effective at determining the physical nature, distances, and chemical properties of newly discovered objects.
While Rubin Observatory excels at discovering and flagging new or changing objects across vast areas of sky, SALT’s strength lies in detailed spectroscopic follow-up — analysing the light from these sources to reveal what they are and how they evolve. Together, the two facilities form a powerful partnership: discovery and diagnosis.
In addition to SALT’s spectroscopic capabilities, the South African Astronomical Observatory has developed an advanced rapid-response capacity through its Intelligent Observatory (IO) programme. The fully automated 1-metre Lesedi telescope at Sutherland operates robotically and is already engaged in time-domain science, routinely observing variable and transient objects.
Lesedi is designed to respond quickly to astronomical alerts, providing early photometric characterisation of newly discovered events. This rapid-response capability complements SALT’s detailed spectroscopic investigations. Together, they form a coordinated system in which Rubin Observatory discoveries can be identified, monitored, and then analysed in depth using SALT’s powerful instrumentation.
South Africa’s geographic location provides a significant strategic advantage. SALT shares access to the same southern sky observed by Rubin, allowing rapid follow-up of transient events shortly after they are detected. This responsiveness is crucial for phenomena that fade or evolve quickly, sometimes within hours or days.
“This is an exciting moment for South African astronomy,” said Prof Rosalind Skelton, NRF-SAAO Managing Director. “Rubin Observatory is transforming how we discover dynamic events in the Universe, and SALT is ideally equipped to investigate them in detail, building on an existing highly successful transient programme. Our ability to respond quickly to these alerts ensures that South Africa will play a leading role in the scientific return from this global endeavour.”
The collaboration strengthens opportunities for South African researchers and students to work at the forefront of international astronomy, contributing to discoveries that may reshape our understanding of the dynamic Universe.
Further updates on the observations and their outcomes will follow as data are analysed.
ENDS
Media Contact:
[Dr Daniel Cunnama]
[d.cunnama@saao.nrf.ac.za]
About the Southern African Large Telescope (SALT)
The Southern African Large Telescope (SALT) is the largest single optical telescope in the southern hemisphere and among the largest in the world. It has a hexagonal primary mirror array 11 metres in diameter, consisting of 91 individual 1-m hexagonal mirrors. It is situated at the South African Astronomical Observatory (SAAO) field station near the small town of Sutherland, in the Northern Cape province. SALT is an international partnership between institutes in South Africa, the United States, Poland, India, and the United Kingdom
SALT Images:
https://drive.google.com/drive/folders/1mHL7ohVnHXZfZROVk6bUbESpp3JRRAGL?usp=sharing
About the South African Astronomical Observatory (NRF-SAAO)
The South African Astronomical Observatory (NRF-SAAO), a facility of the National Research Foundation, is the national centre for optical and infrared astronomy in South Africa. Its primary function is to conduct fundamental research in astronomy and astrophysics by providing a world-class facility to scientists. The NRF-SAAO also promotes astronomy and astrophysics in Southern Africa by sharing research findings and discoveries, and by participating in outreach activities to enthuse citizens about physics and astronomy.
About the National Research Foundation (NRF)
The National Research Foundation (NRF) is an independent statutory body established in accordance with the National Research Foundation Act. Its mandate is to support and promote research through funding, human resource development and the provision of the necessary research facilities to facilitate the creation of knowledge, innovation and development in all fields of science and technology, including indigenous knowledge, and thereby contribute to the improvement of the quality of life of all South Africans.
About the NSF–DOE Vera C. Rubin Observatory
NSF–DOE Vera C. Rubin Observatory, funded by the U.S. National Science Foundation and the U.S. Department of Energy’s Office of Science, is a groundbreaking new astronomy and astrophysics observatory on Cerro Pachón in Chile, with first light achieved in 2025. It is named after astronomer Vera Rubin, who provided the first convincing evidence for the existence of dark matter. Using the largest camera ever built, Rubin will repeatedly scan the sky for 10 years and create an ultra-wide, ultra-high-definition, time-lapse record of our Universe.
NSF–DOE Vera C. Rubin Observatory is a joint initiative of the U.S. National Science Foundation (NSF) and the U.S. Department of Energy’s Office of Science (DOE/SC). Its primary mission is to carry out the Legacy Survey of Space and Time, providing an unprecedented data set for scientific research supported by both agencies. Rubin is operated jointly by NSF NOIRLab and SLAC National Accelerator Laboratory. NSF NOIRLab is managed by the Association of Universities for Research in Astronomy (AURA) and SLAC is operated by Stanford University for the DOE. France provides key support to the construction and operations of Rubin Observatory through contributions from CNRS/IN2P3. Rubin Observatory is privileged to conduct research in Chile and gratefully acknowledges additional contributions from more than 40 international organizations and teams.
Media Pack: