Satellites are placed at a higher risk from fast solar winds than a major geomagnetic storm, a study has found this week.
What did the study investigate?
The study which found the risk from fast solar winds was a collaboration between the British Antarctic Survey and the University of Surrey, UK, and Boston University, USA, and was published in the journal Space Weather. It investigated the risks from space weather to orbiting satellites. The researchers calculated the radiation levels within the Van Allen radiator belts, which are ring-doughnut-shaped zones which wrap around the Earth and trap charged particles. The Van Allen radiator belts contain the geostationary orbit.
The study analysed a years’ worth of satellite data to find that the electron radiation levels at geostationary orbit can remain very high for over five days, even after the speed of the fast solar winds die down. This means that electronic components on satellites can be damaged because they charge up to dangerously high levels.
Why is this research interesting to the satellite industry?
The study was partially funded by the Natural Environment Research Council, UK, as part of the Rad-Sat campaign to protect satellites from space weather. Professor Richard Horne of the British Antarctic Survey, who was the lead author of the study, said: “Until now we thought that the biggest risk to orbiting satellites was geomagnetic storms. Our study constructed a realistic worst-case event by looking at space weather events caused by high-speed solar wind flowing away from the Sun and striking the Earth. We were surprised to discover just how high electron radiation levels can go.”
Will this change the way satellites are used?
The study has advanced scientific understanding of the way satellites are used by confirming the damage that is caused to them by fast solar winds in a worst-case scenario. Professor Horne added: “Electronic components on satellites are usually protected from electrostatic charges by encasing them in metal shielding. You would have to use about 2.5mm of aluminium to reduce charging to safe levels – much more than is used at present. There are well over 450 satellites in geostationary orbit and so in a realistic worst case we would expect many satellites to report malfunctions and a strong likelihood of service outage and total satellite loss.”