We were dog tired after a long day of rowing the heavy rafts 23 miles down the winding river, much of it into the wind. Charlie and Pete had suffered on their raft with a broken rowing frame held together with duct tape. Another 12 miles to go early the next morning to meet our float plane back to civilization. What started out as a pleasant ten-day, 85-mile drift trip down the remote river had become a hard slog as unseasonably dry weather knocked the river’s flow rate way down. Several times we had to walk beside the rafts, dragging them over sand bars that would normally be well under water.
Our very late dinner was C rations, useful for a wilderness trip since they were tightly packaged and self-heating, saving us from cooking and cleanup. Resting weary muscles and nibbling the last chocolate bar, we sat around the small driftwood fire talking about the day. Realizing we had to dig deep to cover the lower stretches of the river in time, we had barely touched our fishing rods despite the superb sport offered by the river’s wild grayling. The night sky offered amazing star views unimpaired by light pollution. By 11 p.m. we were nodding off but refused to hit the sleeping bags because the real show was beginning. The first waves of light green moved above the horizon, followed by yellow, blue, orange and red.
That trip took place above the Arctic Circle on the remote Tagagawik River, 100 miles east of the small Native Alaskan town of Kotzebue beside the Bering Sea. The colors that appeared overhead were of course the northern lights, properly referred to as the aurora borealis. There are few spectacles more stunning and awe inspiring than these brilliant waterfalls of pulsing light. You do not have to journey 6,000 miles to see this amazing display for yourself – as recently as October 12, Maine, New Hampshire and parts of western Massachusetts were treated to a spectacular show. If your travels take you to Argentina, South Africa, New Zealand or Antarctica, you can see the aurora australis displays during our summer months.
The sun is a volatile place, with its outer layer (the corona) estimated at 1.8 million degrees F. The corona is constantly giving off electrically charged particles such as free electrons and positive ions. These particles move out from the sun in all directions in a gaseous form known as plasma, or the solar wind. As the solar wind approaches our planet, the Earth’s magnetic field directs them over the polar regions. When the solar wind reaches the ionosphere 60 to 80 miles above Earth, the charged particles collide with oxygen, nitrogen, helium and hydrogen atoms or molecules, exciting them to higher energy states, and resulting in their emitting light across the full spectrum of colors. The dancing, pulsating nature of the aurora is caused by the erratic movement of the solar wind through our atmosphere.
The best time of year to see the aurora in the northern hemisphere is during the clear nights between December and February, but you may be lucky any time of the year. Normally the northern lights are visible between latitudes 55 and 80 degrees North (Harpswell lies at 43.8 degrees). The auroras can be visible year-round in the right conditions but the long hours of summer sunshine in the polar regions mask the lights from our view. They can show at any time of the day as long as there is darkness, a clear sky, and solar activity. Statistically, midnight and the hours around midnight from 10 p.m. to 2 p.m. are the best time of day to see the northern lights and when most Aurora sightings concentrate. Meteor sightings, on the other hand, are skewed to post-midnight, because of the earth’s orbital velocity: after midnight, the earth tends to run into the meteors, rather than running away from them.
The sun has been observed to go through a cycle of activity that spans 11 years. At what scientists refer to as the “solar maximum,” the sun is particularly active, shedding massive amounts of gas from sunspots or solar flares. Those emissions can trigger powerful geomagnetic storms on Earth, with potential impact on satellite communications and radio or television broadcasts. In extreme events, compasses may give erratic readings due to the excess of electrical charge in the atmosphere. Another impact of those storms is to push the aurora borealis far to the south – on November 5&6, 2001 it was observed in Texas, Arizona and southern California. The last solar maximum was recorded in 2014, but there can be excess solar activity for a couple years following each maximum. It is interesting to note that most of the planets in our solar system and even some comets can host auroras.
Written records from the early 1600s indicate that Galileo deserves credit for coining the term “aurora borealis,” using the Roman goddess of dawn (Aurora) and the Greek name for a north wind (boreas). Today it is easy for us to look at these stunning light shows and thrill to their beauty, secure in the scientific knowledge of their causes. But imagine the impact that a sudden appearance of a particularly bright aurora in a southern location would have had in prehistoric times, even into the Middle Ages, when superstition and myths were the norm. As with solar eclipses, it would have been unsettling at a minimum, even capable of inducing panic in those who had never seen such a phenomenon. Some cultures interpreted the auroras as a sign of impending doom, others saw them as ancestors communicating from the beyond.
Just as there are folks who love to chase tornadoes or eclipses, there are folks who will travel long distances to see peak displays of the auroras. In addition to clear nights, you want to be far away from sources of light pollution. It helps to be a night owl since the lights often reach their maximum intensity well after midnight but before dawn begins to brighten the sky. Keen observers also keep a close eye upon weather reports so they know of a coming peak in solar activity.
As the most northern of the eastern 48 states, Maine is a good place to see the aurora – we certainly have plenty of spots where you can leave the big city lights far behind. Some experts recommend a nocturnal journey to the top of our bigger ski mountains, particularly Sugarloaf, since being at a higher elevation increases the clarity of the air. Locating yourself on the southern shores of some of our big lakes, particularly Sebago and Moosehead, can offer a great view to the north to witness and photograph the aurora over the water. Three places recommended online are the New England Outdoor Center just south of the Baxter State Park entrance, the Caribou-Speckled Mountain Wilderness area, and the Aroostook National Wildlife Refuge, located on the border with Canada.
No matter where you go to see the northern lights, dress warmly and be patient since the spectacle marches to a celestial beat uncontrolled by mankind!