Chris and Ed

Here is the official explanation from NOAA at www.spaceweather.com :

"the interplanetary magnetic field (IMF) near Earth unexpectedly tilted south and sparked a strong geomagnetic storm."

Today's website also has a remarkably long index of websites available from SpaceWeather.com .

Currently I am wondering if the power grid black-out wasn't caused by something solar, possibly beyond instrumentation to pick up. Geomagnetic storms tend to follow X-Class Solar Flares by a few days. The above statement about solar flares and geomagnetic storms was reinforced by data from the Earth and Sun Digest, July 25, 2002, still available at www.bbmessages.com under Hobby BB.

Donald
Donald