09 March 2009
The solar superstorm of 1859
The solar superstorm of 1859 was the fiercest ever recorded. Auroras filled the sky as far south as the Caribbean, magnetic compasses went haywire and telegraph systems failed.
Ice cores suggest that such a blast of solar particles happens only once every 500 years, but even the storms every 50 years could fry satellites, jam radios and cause coast-to-coast blackouts.
The cost of such an event justifies more systematic solar monitoring and beefier protection for satellites and the power grid.
The authors have reconstructed what happened in 1859, based in part on similar (though less intense) events seen by modern satellites.
The gathering storm.
On the sun, the preconditions for the 1859 superstorm involved the appearance of a large, near-equatorial sunspot group around the peak of the sunspot cycle. The sunspots were so large that astronomers such as Carrington could see them with the naked (but suitably protected) eye. At the time of the initial CME released by the storm, this sunspot group was opposite Earth, putting our planet squarely in the bull’s-eye. The sun’s aim need not be so exact, however. By the time a CME reaches Earth’s orbit, it typically has fanned out to a width of some 50 million kilometers, thousands of times wider than our planet.
Will solar superstorm happen again in 2012 ?
The impacts will be on power systems, communication systems, navigation systems and extreme weather.