If you plan to be in Alaska  late May–late July, you can leave the flashlight at home. If you camped at the north pole for a week on either side of summer solstice, the sun would barely appear to move in the sky, frying you to a crisp from the same spot overhead, as if stuck in space. The Arctic Circle, at 67 degrees latitude, is usually defined as the line above which the sun doesn’t set on June 21, nor rise on December 21.
Barrow lies at 71 degrees latitude, 4 degrees and roughly 270 miles north of the Arctic Circle. Here the sun doesn’t dip below the horizon for 84 days, May 10–August 2. (You’ll definitely see, and probably buy, the famous postcard with the time-lapse photograph showing the sun tracing a very mild curve: “going down” in the north-northwest, hovering above the horizon, and “coming up” in the north-northeast.)
Fairbanks , 140 miles south of the Arctic Circle, has 22 hours of direct sunlight on summer solstice, with the sky (if it’s clear) going from a bright orange-blue to a sunset purple to a sunrise pink and back to bright orange-blue. Even Ketchikan , at around 55 degrees latitude and probably the southernmost point on most Alaskan itineraries, enjoys more than 18 hours of daylight, with the starless dusk a paler shade of twilight.
Similarly, in December Ketchikan receives six hours of pale daylight and Fairbanks only three, but at Barrow you wouldn’t see the sun at all for nine weeks.
The explanation for the “midnight sun” lies in the tilted angle of the Earth’s axis. Because the planet rotates off-center, the Arctic Circle leans toward the sun in summer, so a complete 24-hour rotation makes little difference in the angle at which the sun’s rays strike the North Country. However, the rays do have to travel farther, and they strike Alaska  at a lower angle, which you’ll notice: The sun never gets nearly as high in the sky here as you’re probably used to.
Because of the low angle, the rays are diffused over a larger area, thus losing some intensity, which accounts for the cooler air temperatures. And since the sun seems to move across the sky at a low angle, it takes longer to “set” and “rise.” In addition, the atmosphere refracts (bends) the sunbeams more dramatically closer to the poles, which causes the low light to linger even after the sun is down. This soft slanting light is often magical, with sharp shadows, muted colors, and silky silhouettes—a photographer’s dream.
The continual light is a novelty if you’re traveling around Alaska  for just a few weeks, but when you’re there all summer, to paraphrase the commercial, “D-A-R-K spells relief.” Stars? What a concept! Headlights? Oy vey! From early August, though, you start losing daylight quickly, to the tune of an hour a week in Fairbanks . Temperatures drop, berries and rose hips ripen, mushrooms sprout, and there’s the possibility of experiencing one of life’s all-time great thrills: God’s light show, the aurora borealis.
The far-flung Eskimo had a variety of mythical explanations for the lights. Many believed that they represented the spirits of ancestors or animals, while others relegated the lights to malevolent forces. Prospectors preferred to think of them as vapors from rich ore deposits. The Japanese, however, have attributed the most romance to them: A marriage consummated under the lights will be especially fulfilling.
Scientists have lately raised some controversy over particular aspects of the aurora, such as that the lights never dip below 40 miles above the earth (though many northerners swear they’ve seen the lights dancing along the ground); whether or not the lights manifest an electric sound is still a matter of some dissension, and even the experts who believe it don’t know why. But these days everyone agrees that the sun, again, is responsible for the show.
When the solar surface sparks, the energy propels a wave of ionized particles (known as the “solar wind”) through space. When these anxious ions encounter the gases in the earth’s atmosphere, a madcap night of oxygen-nitrogen couples dancing begins. The sun’s particles and the Earth’s gases pair off, with the fastest ions grabbing the highest gases. The ensuing friction causes a red or yellow afterglow. The slower ions infiltrate the lower regions, and those encounters glow green and violet. The waving, shimmering, writhing ribbons of color cannot fail to excite your own ions and gases.
For detailed information on northern lights and predictions of upcoming aurora activity, visit the website of the University of Alaska ’s Geophysical Institute (www.gedds.alaska.edu/auroraforecast ). Other excellent websites include www.pfrr.alaska.edu/aurora  and the kid-friendly www.alaskascience.com/aurora.htm .
A number of lodges in the Fairbanks  area have geared their winter season for people who come to view and photograph the northern lights, especially Chena Hot Springs Resort  and Spirit Lights Lodge in Bettles. Many Fairbanks hotels will provide aurora wake-up calls on request.