Engineering News

The phenomenon known as space weather was a cause for concern regarding the new generation technology systems that enabled the Internet of Things (IoT), which underpinned the Fourth Industrial Revolution (4IR). So warned South African National Space Agency (Sansa) Space Science MD Dr Lee-Ann McKinnell at Sansa's second Space for National Development Conference, in Pretoria, on Wednesday.

"Space weather is a risk to the Fourth Industrial Revolution," she said. Space weather effects will have to be taken into account in the development and implementation of these technologies. Today, space weather science is about "protecting our technology for tomorrow".

Space weather can be defined simply as conditions on the Sun, in space and in the solar wind that affect technological systems orbiting or on the Earth. The solar wind is the constant stream of particles that escape from the Sun and radiate throughout the Solar System. 

Light from the Sun takes just over eight minutes to reach the Earth. Space weather specialists observe it using a range of different wavelengths, as each of these wavelengths provides different information as to what is happening on the Sun. This information is needed to try and predict space weather. 

"When the Sun sneezes, the Earth catches cold!" she observed. The drivers of space weather are Solar Flares, Solar Energetic Particles and Coronal Mass Ejections. While these events usually happen separately, they can occur, and have occurred, at pretty much the same time.

Solar Flares take eight minutes to reach the Earth, she explained. They increase ionization in the atmosphere and disrupt High Frequency (HF) radio communications.

Solar Energetic Particles take about 15 minutes to reach the Earth. This also increases ionization in the ionosphere, particularly in high latitudes (that is, approaching the poles). They also disrupt HF radio communications but, in addition, increase radiation exposure for astronauts and for anyone flying above 30 000 feet (roughly 10 000 m) in altitude.

Coronal Mass Ejections take from one to four days to reach Earth. They accelerate particles within the magnetosphere and ionosphere. In addition to disrupting HF communications, they can degrade and disrupt the performance of satellite navigation systems, and affect terrestrial electric power grids and pipelines.

Space weather is a phenomenon that affects the entire world. But, because of differences in location, topography and infrastructure, it affects different regions differently. That is why a network of regional space weather centres is required, and all regions now have such centres. The Sansa Space Science division at Hermanus in the Western Cape province is both Africa's designated regional and only space weather centre.

Feeding into the Hermanus Centre is a very extensive network of ground-based sensors, covering South Africa, some neighbouring countries and even extending into the Antarctic. "We [Sansa] are very good at measuring space weather from the ground," reported McKinnell. "We've basically turned Southern Africa into a geophysical research network."

However, currently, this network is focused on research. That is, it doesn't provide data in real time. It is going to be upgraded into an operational network, which will provide data in real time. That data will serve both to help in the making of space weather predictions and in driving forward research. 

Research, she pointed out, underpinned everything. Sansa had a strong space science research team, and was going to strengthen it further over the next three years.

Sansa Space Science is one of only 19 space weather centres around the world. It is also one of only five space weather forecasting centres for aviation, designated by the International Civil Aviation Organisation (ICAO). This month has seen the start of the implementation of the new ICAO rule (passed in 2018) that space weather information for the whole flight route for intercontinental flights had to be provided to operators and flight crew. This rule will come into effect at the regional level in 2022. Sansa is contributing to the global space weather data for civil aviation and will provide the regional information for flights over Africa.