South Africa Celebrates 20 Years of SALT: Africa’s Giant Eye on the Universe

The Southern African Large Telescope (SALT) — the largest optical telescope in the Southern Hemisphere — marks its 20th anniversary this year, commemorating two decades of groundbreaking astronomical discoveries and scientific excellence. The milestone celebration will take place on Monday, 10 November 2025, in Sutherland, Northern Cape, where the telescope stands as a symbol of Africa's scientific ambition and global collaboration.

Deputy Minister of Science, Technology and Innovation, Dr. Nomalungelo Gina, will deliver the keynote address at the event, which will gather leading astronomers, international research partners, and science leaders to reflect on SALT's impact on astronomy, technology, and education across the continent.

A Two-Decade Legacy of Discovery

Since its inauguration in 2005, SALT has stood as Africa's "Giant Eye on the Sky", revolutionising the continent's capacity for world-class astronomical research. Located at the National Research Foundation's South African Astronomical Observatory (NRF-SAAO) in the Karoo desert, SALT was the first large-scale international science infrastructure of its kind in sub-Saharan Africa.

Over the past twenty years, the telescope has played a central role in major astronomical discoveries, including:

• The identification of new exoplanets orbiting distant stars;

• Observations of the optical afterglow of neutron star mergers — providing insights into gravitational waves;

• Detailed studies of galaxies billions of light-years away, offering glimpses into the universe's earliest epochs; and

• Research on the chemical composition of stars, helping scientists trace the origins of cosmic elements.

The Department of Science, Technology and Innovation (DSTI), under which the NRF operates, said the facility continues to "enable South Africa to remain internationally competitive in astronomy well into the 21st century and provides a focus for the development of basic space science on the African continent."

A Symbol of African Scientific Excellence

Built through a multinational partnership between South Africa and global research institutions, SALT is modelled after the Hobby-Eberly Telescope in Texas, USA, but with enhanced instrumentation and a mirror array designed for optimal precision under southern skies.

Its 11-metre hexagonal mirror — composed of 91 individual segments — allows astronomers to capture light from distant cosmic objects with extraordinary sensitivity. From its remote high-altitude location in Sutherland, where skies are among the clearest and darkest in the world, SALT contributes to both pure science and applied technological innovation.

Over two decades, SALT has nurtured collaboration between South African scientists and international researchers from the United States, Germany, Poland, India, the United Kingdom, and New Zealand, among others.

Driving Skills, Innovation, and Inspiration

The 20th anniversary celebration will not only highlight SALT's scientific achievements but also its impact on human capital development. The facility has trained generations of South African astronomers, engineers, and data scientists, many of whom now play leading roles in international research.

According to the DSTI, SALT has been instrumental in building local research capacity, stimulating STEM education, and inspiring young Africans to pursue careers in space science. The telescope's success has also strengthened South Africa's role in global astronomy networks, complementing projects like the Square Kilometre Array (SKA) — the world's largest radio telescope under construction across South Africa and Australia.

"SALT has not only expanded our understanding of the cosmos but also strengthened South Africa's leadership in science and technology. It stands as a beacon of what sustained investment in innovation can achieve," said Deputy Minister Dr. Nomalungelo Gina.

A Vision for the Future of Astronomy in Africa

As South Africa celebrates 20 years of SALT, the event also marks a moment to look forward. The telescope remains central to the country's Astronomy Geographic Advantage (AGA) Programme, which aims to consolidate Africa's reputation as a hub for world-class space science infrastructure.

The DSTI reaffirmed its commitment to expanding research opportunities, developing indigenous technologies, and supporting cross-border scientific partnerships that leverage SALT's capabilities for future exploration.

In addition to reflecting on past accomplishments, the celebration will feature panel discussions, scientific presentations, and exhibitions showcasing SALT's contributions to astronomy and society.

The anniversary serves as a reminder that SALT's success is not just a triumph of technology, but a testament to South Africa's vision of science as a driver of progress, collaboration, and continental pride.

"Africa's Giant Eye on the Sky continues to remind us that through science and innovation, our continent can gaze far beyond its horizons — and reach for the stars," the DSTI said.