Aurora borealis in Alaska, 2006. Courtesy of Dick Hutchinson.
One of the most popular posts we ever did on this site was about the aurora borealis (also known as the Northern Lights) that Meriwether Lewis and William Clark observed in the fall of 1804, when they were getting settled at their winter camp near the Mandan villages in North Dakota. The Little Ice Age explains how the aurora borealis that year may have been especially vivid due to the extreme climate conditions that prevailed that winter. Clark’s thermometer, which is considered reliable, routinely reached -40. After a while, as Clark wrote, a temperature of -9 “was not considered cold.”
Clark wrote a wondering passage about his first sight of the incredibly beautiful natural phenomenon:
last night late we wer awoke by the Sergeant of the Guard to See a nothern light, which was light, but not red, and appeared to Darken and Some times nearly obscered, and divided, and many times appeared in light Streeks, and at other times a great Space light & containing floating Collomns which appeared opposite each other & retreat leaveing the lighter Space at no time of the Same appearence. — William Clark, November 6, 1804
The aurora borealis is caused by solar flares which interact with the earth’s magnetic field. The subatomic particles of the flare are directed in streams to the earth’s magnetic poles, appearing in the sky as colorful trembling arches and streaks in a variety of colors. And as it turns out, many more of us will soon have the chance to witness what Lewis and Clark saw, because in 2013, the aurora borealis will be visible further south than it has been in over a decade.
Aurora borealis over Norway, by Ole C. Salomonsen
The reason is a phenomenon called the solar maximum, a period of increased activity by the sun that results in solar flares, intense magnetic loops (sunspots), and the flipping of the sun’s North and South poles. NASA scientists have issued varied predictions on how strong next year’s solar max is expected to be. Depending on how strong they are, the geomagnetic storms could cause disruptions in our cellphones, television, GPS, and power grids, and even expose air travelers to high degrees of radiation.
It will also produce fabulous auroras. The most powerful solar storm ever recorded came in 1859, and produced auroras visible as far south as Los Angeles and Mexico. The storm caused widespread disruption to telegraph lines, and it was reported that gold miners in the Rocky Mountains could work through the night and that townsfolk in New England could read a newspaper by the brightness of the lights (only in New England would people read the paper during the aurora borealis).
While next year’s storm isn’t expected to be that strong, it shouldn’t be underestimated. It is difficult to predict the aurora borealis, but it should be visible in many parts of Europe and the United States, and spectacular in places like Alaska, northern Canada, Siberia, Greenland, Iceland, Norway, Finland, and Sweden. The best months to see the aurora are August-April, with peak viewing around the equinoxes in September and March.
The Norwegian photographer Ole C. Salomonsen is an aurora chaser. The amazing video above is called Celestial Lights. Don’t skip this one.
