The Space Science division of the South African National Space Agency (Sansa) has officially inaugurated its ‘24/7’ space weather forecasting capability, at its facility in Hermanus (southeast of Cape Town) in the Western Cape province. The inauguration was conducted by South African Higher Education, Science and Innovation Minister Dr Blade Nzimande on Thursday.

In his address, Nzimande reported that the setting up of the capability, which included the construction of a dedicated building and ancillary structures and systems (including a generator to provide power during ‘loadshedding’, when the national electricity utility Eskom implemented rotating power cuts owing to inadequate supply), as well as training staff, had required an investment by Sansa of R107.5-million over three years. He highlighted that Sansa had developed the business case for the ‘24/7’ capability in 2019, and that the programme had been successfully implemented despite taking place during the Covid-19 pandemic.

“Space weather can be defined most basically as the impact solar storms have on Earth’s atmosphere and below,” explains Sansa Space Weather Centre MD Dr Lee-Anne McKinnell. This impact can include damaging satellites in Earth orbit, which could disrupt telecommunications and satellite navigation (‘satnav’ or GPS) services, affect airliners in flight, and even damage power transmission lines. Space weather is a matter of day-to-day practical importance, as well as a fruitful sphere of scientific enquiry.

Sansa Space Science had a limited ability to undertake space weather forecasting for many years, but lacked the capacity (in both personnel and equipment) to do it on a 24/7 basis. But those entities (including airlines, air traffic management agencies, telecommunications companies, and satellite operators) which need such information, need it 24/7. Moreover, they need it on a global basis. Sansa was and is the only agency in Africa with space weather forecasting capability.

Elevating this capability to a 24/7 basis is thus a very important contribution to filling a major ‘gap’ in global coverage and strengthening space weather forecasting worldwide. And Sansa is planning, in partnership with other African countries, including Kenya, Nigeria and Zambia, to close this gap entirely.

“We get our data in near real-time,” she elucidates. “Our data sources are solar observation satellites and a ground-based instrumentation network. This network belongs to Sansa, and is spread across the country, plus the [Gough and Marion] islands and Antarctica. We’re going to expand it, across Africa. As a recognised regional centre we need to be able to forecast for Africa, so we need to bring in data from across the continent. This expansion will be jointly funded by Sansa and our African partners, which include space agencies and universities.”

The ground-based instrumentation network uses three kinds of sensors. The two most common types are magnetometers and satnav receivers. The third, less common, type, is an ionosonde system, which is a ground-based radar system for measuring the ionosphere. In addition, Sansa Space Science has its SuperDARN radar system in the Antarctic. (SuperDARN stands for Super Dual Auroral Radar Network.)

“The SuperDARN radar gives us very important information because it looks up at Earth’s magnetic field lines, giving us a window into ‘geospace’,” she points out. “Geospace is the near-Earth space environment.”

“We normally issue one [space weather forecast] bulletin a day,” reports Sansa space weather researcher Dr (Ms) Rendani Nndanganeni. “But if, for example, a solar flare occurs, we issue a warning as well.” The space weather centre now has eight forecasters and is aiming for 12. There are two shifts, day and night. Day shift requires one forecaster, because she (or he) can be backed up by the division’s space science researchers, but the night shift requires two, to back each other up, as no other scientific support is normally available at night.