The dramatic advances in technology that have taken place over the past 20 years have made all countries, including South Africa, more vulnerable to space weather. Adverse space weather can disrupt satellite navigation systems (like GPS), satellite communications, long-range radio signals and even, in extreme cases, electrical transmission networks and long-distance pipeline systems.

As a result, the South African National Space Agency's (Sansa's) Space Science division, which is responsible for monitoring space weather (it operates the national Space Weather Centre), is now seeking to make local industry and government aware of the dangers posed by space weather. "We have ever greater dependence on technology systems," pointed out Sansa Space Science MD Dr Lee-Anne McKinnell at the Sansa Space Weather Information Day in Pretoria on Tuesday. "This technology infrastructure is vulnerable to space weather effects."

"Space weather refers to conditions on the Sun, the solar wind, magnetosphere, ionosphere and thermosphere that can influence the performance and reliability of space-based and ground-based technology systems," she explained. The areas of particular concern for South Africa are aviation, electrical power, satellite navigation, satellite operations and communications.

"We have designed our space weather programme around its relevance to the country," stated McKinnell. "We do constant monitoring of space weather, with a 24/7 on-call system. We also do an alert and warning system. We also interpret the data to obtain useful information. We provide an interpretation of this data. We can also do space weather training and needs analysis [for industry]. Our aim and our motto in our Space Weather Centre is to provide the right information in the right format, at the right time, to the right people."

The main space weather phenomena are solar flares, solar energetic particles (protons, electrons and helium ions) and Coronal Mass Ejections (CMEs). Solar flares can disrupt high frequency (HF) radio communications and satellite communications. They take eight minutes to reach Earth. Solar energetic particles can reach Earth in 15 minutes to a few hours, depending on their severity. With these, ionizing radiation penetrates the atmosphere, satellites can be damaged and HF communications are disrupted. They are dangerous for astronauts. CMEs take one to four days to reach the Earth. Most do not come towards Earth. Those that do are called Geo-effective and affect HF communications, satellite navigation systems, increase the drag on satellites (causing orbital decay) and generate auroras. CMEs also create Geomagnetically Induced Currents, which affect electrical power systems, oil pipelines and even undersea cables.

The purpose of the Space Weather Information Day was not only to brief government and industry about space weather and Sansa's capabilities, but also for Sansa to ascertain the needs of those departments and companies.