Huge Geomagnetic Storm Descends on Earth

Release Date: 
Friday, November 21, 2003


The second largest geomagnetic storm on record has allowed people in mid-latitudes to see the aurora borealis and could possibly make for outstanding aurora viewing over Alaska through Saturday, November 22.

The geomagnetic storm, which began at about 11 a.m. Alaska time on November 20, 2003, was the largest recorded storm since a storm in March 1989 knocked out power to the entire province of Quebec. Though it is not known if the November 20 storm affected power grids, scientists at the University of Alaska Geophysical Institute did receive reports of intense aurora activity from people in Switzerland, Germany, Italy and Austria.

A sunspot that generated huge solar flares in October and early November is again the driver of the geomagnetic activity. Because the sun rotates every 27 days, the sunspots that generated huge solar flares in late October are now rotating back toward Earth. On November 20, the sunspot erupted in a coronal mass ejection, which sent a burst of charged particles toward Earth. Earth’s magnetic field happened to be aligned in a favorable way for a geomagnetic storm.

“We just happened to get a gust of solar wind that hit the Earth very hard,” said Dirk Lummerzheim, a research professor who studies the aurora at the Geophysical Institute. 

Though geomagnetic storms can induce currents in long conductors, such as power lines or the trans-Alaska pipeline, those effects are rare, but outstanding auroras are not. Geophysical Institute aurora forecaster Charles Deehr predicted maximum auroral activity through Saturday, meaning that auroras could occur all across the US, northern Europe, and southern Australia and New Zealand. The aurora forecast can be found at