The northern lights, or aurora borealis, are a frequent visitor at high latitudes during the long nights of winter. In central and northern Alaska, they can usually be seen on more than half of clear nights when skies are dark enough. (During the summertime, “polar day” means the sun never sets, making it impossible to see the spectacle.)
Trying your luck in the dead of winter is ordinarily the best bet, but it’s not for the faint of heart. Fairbanks hasn’t recorded a temperature above zero in a week.
Despite the frigid air, clear skies and calm winds have allowed for perfect aurora spotting. Monday night featured shimmering curtains of green, tinged with delicate purple on top. Some photographers even captured corona phenomena, or ebbing eddies of aurora plasma dancing directly overhead like glow-in-the-dark whirlpools.
The northern lights are most frequently visible every 11 years or so during peaks in the solar cycle. The solar cycle charts the number of sunspots, or bruiselike discolorations, on the surface of the sun; sunspots pulsate with energy, occasionally hurtling high-frequency particles and magnetism into space. When that energy reaches the Earth, some of it is transformed into visible light — a.k.a. the aurora.
Currently we’re exiting solar minimum, when long, spotless stretches can persist for weeks and the sun is eerily quiet. In the years ahead, more sunspots are likely to crowd the solar disk, boosting the chances for solar storms and the opportunity to enjoy the northern lights.
Most experts predict that the coming solar cycle will be run of the mill, but a few are gambling that this could be the biggest solar cycle in generations.
Lately, Fairbanks has been the place to be. Luke Culver, a meteorologist at the local National Weather Service office there, captured a mesmerizing time lapse of the ephemeral display:
The office’s Doppler radar dome, used to track rain, snow and storm systems, can be seen in the foreground against the luminous green backdrop.
Culver shot similarly remarkable photos during an episode of the northern lights in early January:
“This is my second full winter up here, and really because it’s near solar minimum, there haven’t been too many shows,” Culver said. “Last year there were four or five like this, this year one or two so far.”
Monday night’s display was partially captured by the Suomi NPP satellite, which orbits the poles and peers down on Earth. In a slice of imagery it took, curls of the aurora can be seen near the border of Nunavut and the Northwest Territories in Canada.
“It was about 25 below and 10 to 15 mph [of] wind, so the wind chill was definitely cold,” Culver said. “I jumped back in the car after 10 minutes. You can’t have super thick gloves on to use the camera … but your hands get cold pretty quick.”
Aurora season extends another few months in Fairbanks before the nearly endless daylight will sully the show. The sun doesn’t rise until after 9 a.m. at the beginning of February, with sunset creeping back past 5 p.m. The best time to catch the aurora is arguably around the equinox.
That’s when virtually any little perturbation in the Earth’s magnetic field can generate spectacular displays. Odds are the folks in Fairbanks will be looking up.