How a severe solar storm could leave a lasting impact on our world

Sean T Smith explores the repercussions of such a storm on the infrastructure that underpins so much of our society

Coronal mass ejections are massive expulsions of magnetised plasma and solar particles (Nasa/Goddard/SDO)

Exactly 10 years ago, our planet dodged an electromagnetic bullet that had been fired from the heart of the sun. Coronal mass ejections or CMEs are massive expulsions of magnetised plasma and solar particles that routinely erupt from the solar surface. Most drift off harmlessly into space but on 23 July 2012, the largest solar storm in a century catapulted through our orbit missing the Earth’s position by just nine days.

Had it hit home, the likely abandonment of the London Olympics would have been the least of our problems. The giant geomagnetic storm triggered by a direct hit could have fried electrical circuits, taken out communication systems and crippled national grids across the world; the global economy would only now be emerging from the aftershocks of such a worst-case scenario.

According to Mike Lockwood, a professor of space environment physics at Reading University, giant geomagnetic storms do not pose a direct threat to human life but the subsequent chaos could certainly become life-threatening.