The National Research Foundation’s South African Astronomical Observatory (SAAO) in Sutherland in the Northern Cape now hosts one of four telescopes that form part of the Nasa-funded Atlas asteroid alert system.
Atlas, or Asteroid Terrestrial Impact Last Alert System, is specially designed to detect objects that approach very close to Earth — closer than the distance to the Moon, up to about 240,000 km away.
A $5-million grant to the University of Hawaii from Nasa’s Near-Earth Objects Observations programme, now called the Planetary Defense Coordination Office, kicked off the system’s development back in 2013.
The first two telescopes on the islands of Haleakalā and Maunaloa, which are about 160km apart, became fully operational in 2017.
The South Africa-based telescope, Atlas 3, and another installation at El Sauce Observatory in Chile resulted from a further $3.8 million in funding granted in August 2018.
“The two locations were selected for their access to the southern part of the sky as well as their time zones, which allow for night observation when it is daytime in Hawaii,” the Department of Science and Innovation explained.
Combined, the four telescopes will now be able to scan the entire night sky around the clock for objects that could collide with the Earth.
Atlas 3 was installed in November 2021 by an SAAO team that included Electronic Technician Willie Koorts.
Koorts published a detailed video of the process on YouTube.
After arriving in two large crates, the mount and telescope had to be lifted into a dome at the Sutherland facility and fitted precisely.
He explained the system combined a relatively simple telescope with a powerful 110MP CCD camera capable of detecting a match flame in New York when viewed from San Franciso.
The telescope’s field of view is also 15 times the diameter of the full Moon.
Koorts said the system could provide a one-day warning for a 30-kilotonne “town killer”, a week’s notice for a 5-megatonne “city killer”, or three weeks’ forewarning for a 100-megatonne “county or province killer”.
Atlas can also search for dwarf planets, supernova explosions, and flashes of light when a star is consumed by a supermassive black hole in a distant galaxy.
As of November 2021, Atlas had discovered around 700 near-earth asteroids, 70 potentially hazardous asteroids, 65 comets, and nearly 10,000 supernovae.
Science and innovation minister Blade Nzimande said the South African installation had already discovered its first near-Earth object, as shown in the image below.