Massive sunspot AR 1785 – eleven times the diameter of earth – now faces our planet with potential for some nasty flares. Space weather forecasters at NOAA predict a 55% chance of M-class and 10% X-class for today.
Luckily earth has the magnetosphere which deflects solar wind and concentrates solar energy at the magnetic pole. Scientists have known for a long time the magnetosphere wasn’t perfect; just as the ozone layer develops “holes”, our magnetic shield is prone to “cracks”. Anyone lucky enough to see an aurora has witnessed the power of electrically charged solar winds.
In 1961 scientist Jim Dungey theorized these cracks occurred when the solar energy arrived packing a magnetic field that travelled in the opposite direction from our magnetic field. We now know these cracks can remain open for hours, allowing billions of electrically charged particles to light up the sky. Severe solar storms can wipe out satellites, communication, and power.
AR 1785 will most likely blast tons of plasma into space before fading away. Geomagnetic storms will rage – airplanes might change course to avoid radiation, auroras will dazzle, and few will be the wiser. I don’t lose sleep over space weather, I just wish more people understood the implications of a direct hit through an unlucky crack that could plunge us into darkness for months.
Photo by Taichi Nakamura of Dunedin New Zealand – southern hemisphere auroras when earth passed through a region of southward magnetic field, opening a crack in the magnetosphere on July 6.