There's a lonesome outpost in the Alaskan interior where scientists work in wool slippers and all-nighters are standard procedure, where sunlight is scorned and darkness cherished for the promises it holds. That outpost is the science center at the Poker Flat Research Range, a rocket-launching facility in the hills 30 miles northeast of Fairbanks. Poker Flat is one of the world's premier centers for studies of the aurora borealis, the electromagnetic light show that graces the subarctic firmament almost every night of the year.
Perched on top of a low rise with a uniform view of sky, snow, and spruce, the center sometimes teems with humanity, as researchers come from around the globe to grab a glimpse of the luminous curtains and rays that dance to a silent madrigal far above the tundra. Tonight, though, it's the regulars from the Geophysical Institute of the University of Alaska at Fairbanks. They'll while away the wee hours swapping stories, watching movies, trading computer tips, and waiting for a phantom stream of light.
Coffee thickens on the burner in the kitchen, sepulchral light spills from exit signs in the darkened hallways, instruments and monitors hum in the control room upstairs, and stars bear down on the glass walls of the center's observation room. At peak aurora season, fanatics like Hans Nielsen, a fiftysomething Dane, keep vigil in this place every night for weeks on end. "When I get on this schedule, I can't remember one night from the next," he confesses. "It all becomes a blur." Not that he's complaining. Like most of his colleagues, Nielsen has a special fondness for the northern lights and an awe of the sort that has inspired thousands of years of folklore and myth.
"No pen nor pencil can portray its fickle hues, its radiance, and its grandeur," polar explorer William H. Hooper said of the aurora, but literal translations of its various names in other cultures hint at its magnificence: The Romans called it "blood rain," the Chinese "candle dragon," Eurasians "wind light." To the Inuit, the aurora borealis was the highest level of heaven, where the dead danced. "Streaks of light toss about with abandon," goes a typical account. "Suddenly, for a second, all light melts away and the sky is full of darkness. Just as quickly the lights blossom again in pulsating waves and arcs, and then, as if to test the credulity of man, giant draperies of it wash by in undulating movements across the whole heavens, sometimes stabbing the ends of their folds toward the earth, dripping with the green of grass or the red of blood." The technical details of auroral activity aren't quite as poetic. In the 1950s, scientists began to understand that the aurora borealis and its southern conjugate, the aurora australis, are generated by the interaction of charged particles streaming from the sun and the magnetic field that surrounds Earth. The geomagnetic field deflects most of the deadly particle stream, but in doing so it gets swept out into a comet-shaped envelope, called the magnetosphere, in which some of the particles are trapped. Electromagnetic forces energize the trapped particles and draw them down into Earth's atmosphere at the polar regions, where they collide with atoms and molecules of gas, producing light.
