Solar storms could cripple modern life
The solar flare was massive. It catapulted a giant blast of plasma across the solar system, easily punching its way into our protective magnetosphere. Seconds later it bombarded the Earth itself, a storm of particles that may have been powerful enough to send advanced civilisations back to the Iron Age.
Luckily though, it was 660BC so that’s where we were anyway.
Scientists studying ice cores have found evidence of a solar storm many times stronger than anything seen in the electronic age. They said that depending on the form it took, a repeat could cripple communications.
‘‘This was a high level of particle radiation, ten times more than has been observed in the last 70 years,’’ Raimund Muscheler, of Lund University in Sweden, said. ‘‘If that solar storm had occurred today it could have had severe effects on our high-tech society. These particles would possibly damage infrastructure in space, could be a hazard to astronauts on the International Space Station and would result in high radiation for people in planes.’’
Because they were looking so far back in time, he and his colleagues were able to spot only a signature of high- energy proton particles but if, as he suspects, these also came with a soup of lower-energy particles, the effects would be more wide-ranging.
‘‘These can produce power surges in electricity grids, damage transformers and cause blackouts,’’ he said.
The sun is continually ejecting tonnes of charged particles that fly across the vacuum of space and bombard the Earth. Most of the time we are protected by our magnetic field, which pushes them around the poles where they are seen as the northern or southern lights.
Occasionally, enough are released that they overwhelm the planet’s defences. Then, they can interfere with electronics in satellites and on Earth.
Although in the past humans would probably not have noticed them, they leave a signal in trees and ice cores. When the higher energy particles hit the atmosphere, they cause miniature nuclear reactions, creating new atoms.
This can be seen in the carbon isotopes stored in trees and in the beryllium and chlorine isotopes laid down in ice. That was the signal spotted by Professor Muscheler and his colleagues, who described their findings in Proceedings of the National Academy of Sciences.
Their research tallies with recent work showing a similarsized solar storm in 774AD. This suggests that such storms are not one-offs, and, said Muscheler, that we should adjust our idea of what the sun is capable of. ‘‘We have direct radiation measurements from the sun for about the last 70 years,’’ he said.
‘‘That is basically the window we understand directly. What we see in the paleorecord is that the sun can do much, much worse things.’’