IN FAIRBANKS, THE LIGHT FANTASTIC

Just south of the Arctic Circle, as spring arrives, the forecast on the front page of the newspaper is cheery: "Another sunny, chilly day." That means we're looking for a high of 12 and a low of -20.

The low end of that forecast means something to me and my fellow travelers: We will spend the midnight hours and beyond outside, in the wind, on a mountaintop 20 miles north of town. It also matters that the skies will be clear. We are here to see the Northern Lights, the aurora borealis, the greatest light show on Earth. (Actually, it is one of two such shows. Its mirror version, aurora australis, goes on at the South Pole, where, it should be noted, -20 would be warm.)

Fairbanks, population 32,650, is a hunkered-down town between the Arctic Circle and Mt. McKinley. That puts it right in the middle―the interior, as it is called―of the country's largest and, some would say, most inaccessible state.

Fairbanks passes muster in the lodging and dining categories, but that's not why people come here. They come for a taste of life on the edge of the planet, where there are vast expanses of unsettled land and, in summer, sunshine at midnight. During my visit in mid-March, Fairbanks was hosting the North American Championship Sled Dog Races and the World Ice Art Championships. The races were downtown, the ice sculptures next to my motel. Both were genuine attractions, and I took them in, but they were not my main reason for coming.

I was here, like increasing numbers of visitors, to look at the sky.

Aurora seekers bring with them an interest in nature, in astronomy, in physics, in spiritual enlightenment, in photography or in none or all of the above. I fall in the all-or-none-of-the-above category. I caught aurora fever from a friend in San Diego who had heard about the trip at an astronomy lecture. For her, it was all about the aurora; for me, it was also an excellent excuse to make good on my long-standing intention to see Alaska. The five-day trip came with no guarantee that we would see an aurora, but it was timed to be a good bet. We signed on.

Although auroras can be devilishly unpredictable, this year and next are expected to be a time of extraordinary solar activity and, therefore, extraordinary auroras. Spring and fall near the equinox are considered the best times. Those seasons strike a balance between two important factors: dark skies and cold weather. In summer, it's light all night so the aurora doesn't show up; in winter, it is so cold that even the locals don't like to venture out much because temperatures can sink to -60. Cloud cover, which can occur any time of year, is always a wild card.

A spring trip has an intangible benefit: Freshly freed from winter, Alaskans are happy to see you.

Viewing conditions should be good through this month. There is still enough nighttime, and temperatures are on average 20 degrees warmer than in March. Like the climate, daylight changes quickly here, increasing or decreasing six to eight minutes a day.

Fairbanks is a great place to see and study the aurora, both for tourists and scientists. The aurora occurs in a ring around the magnetic North Pole, and most of the time, Fairbanks is right under the auroral ring. When there's a lot of solar activity, the size of the ring expands, which means that occasionally there is a great show in lower latitudes, even, say, in Iowa or New Jersey. In recent weeks, the aurora has really been going wild: People have caught glimpses as far south as Palm Springs and Phoenix.

Solar storms and flares are key to aurora displays because they send electrically charged particles from the sun hurtling into space, some of them toward Earth. Those that get caught up in Earth's magnetic fields end up unleashing tremendous energy in the form of light, and sometimes wreak havoc on radio transmissions and power plants.

Like tall, thin sheets shifting in the breeze, the aurora moves in swirls across the sky, following the lines of the magnetic field. The light feels close but isn't really. The bottom edges of those sheets are 60 miles above Earth, and the light extends several hundred miles upward. The swirls can move from horizon to horizon, or in smaller sweeps. White and green are the predominant colors, with touches of pink and sometimes red. It's difficult to capture on film exactly what the eye sees; film can pick up additional color because of long exposures and, of course, can't relay the motion.

My group was getting some lessons in how all this works from scientists at the University of Alaska's Geophysical Institute who study the aurora, including tracking it by radar and launching rockets into it from the Poker Flat Research Range outside town. We heard about the science of the aurora from Neal Brown, founding director of the Poker Flat facility, who now does educational outreach at the institute, and we learned about photographing the aurora from Jan Curtis, a meteorologist who has fallen under its spell.

The aurora and Alaska itself have a way of casting spells. On the flight here, the cloud cover cleared just in time for a breathtaking view of Prince William Sound in the Gulf of Alaska. Glaciers seemed to flow like rivers off the snow-covered mountains and into the water; sheets of ice floated in the lake-like calm; tree-covered islands were scattered below. Later we flew right next to Mt. McKinley, at 20,320 feet the tallest and most majestic mountain on the continent.

The extraordinary history of Alaska, before and after it gained statehood in 1959, is laid out in well-designed exhibits at the University of Alaska Museum on the Fairbanks campus. Our group spent an afternoon exploring it, and I found a neat book in the museum store that talks about the little airstrip, carved out of wilderness in World War II, where my dad was stationed as a radio operator. I had heard stories from him about Alaska, about the long nights and deep freezes; of the wild terrain and the men who lived in it. And I'd heard more modern tales from my brother and sister-in-law, who lived in a valley outside Anchorage in the '80s. Always, this place has been fodder for storytelling and has attracted people on a quest for something.

Fairbanks has seen its fortunes rise and fall numerous times, mostly on the discovery of gold and oil. There are old mining operations in the surrounding hills, and the Alaska Pipeline runs right by town on its 800-mile path from Prudhoe Bay on Alaska's North Slope to Valdez in Prince William Sound.

In many ways, the cold shapes the culture of Alaska. It demands respect at every move. All of us aurora-trackers were loaded down with warm clothes: parkas, down vests, ski pants, long underwear, thick wool socks. We ended up wearing everything we had brought―all at once―on our nighttime outings.

Even appetites tuned to salads and fusion cuisine knew they weren't in California anymore: The motel where we stayed served a complimentary breakfast that included biscuits and sausage gravy, and we lapped it up.

There were about 35 in our group. We flew in from Southern California, Utah, Texas, Virginia, Washington, Connecticut and Florida. Among us were a mapmaker, an anesthesiologist, a building contractor, an urban planner, a musician, an engineer and a former mayor. Arrangements were handled by Arizona-based TravelQuest International, which hooked up with Dennis Mammana, chief astronomer at the Reuben H. Fleet Science Center in San Diego, to organize the trip.

Each night at about 8 o'clock, our group boarded a bus for the half-hour drive north to Skiland, open at that hour for aurora watchers, not skiers. The view of the sky was wide open. We would stay outside as long as we could stand it, then go inside to get warm, important because it was at least -20. Everything was kept dark; light fixtures and flashlights were covered with red filters, as in a photo darkroom. Others were gathered here too: tour groups from Japan and a scattering of people who had driven their cars up the mountain.

We were dressed as close to polar bear-style as we could get, so thickly layered that we hardly recognized one another. Anywhere else we wouldn't be caught dead in a facemask, but here we couldn't do without them.

Most members of our group brought cameras; capturing the aurora is part of the appeal of being here. Photographing the aurora, though, is much different from taking the usual vacation snapshots. Fifteen-second exposures are typical, so tripods are a must. The extreme cold is brutal on film (advancing and rewinding too quickly can cause the film to break), and at these temperatures, batteries die quickly. (Cameras that don't rely on batteries are recommended.) The ultra-low humidity is a hotbed for static electricity, which can leave annoying flashes on film. Last but not least is the elusive nature of the subject. It is nothing more substantial than shifting light.

The three nights our group went out yielded very different experiences. The first night, there was a lovely display that delighted us; we actually saw the great lights we had come so far to experience. The third night, there was little activity in the sky, but camaraderie was high, partly because the second night still loomed large in our minds. Night No. 2 was spectacular in every way. For nearly five hours the sky was alive with light: graceful, sensual and mesmerizing all at once.

In every direction were the colors and formations for which the aurora is known. Light shifted like piano keys. Curtains of light blew in the wind. A tent of light rose above.

Near midnight there was the crown jewel, a corona. Ribbons of light merged in a swirling apex straight above. We all tipped our heads back to drink it in. There was a moment of pure, shared awe, then words as each person tried to put it into context. It was both out of this world and strikingly of it: a giant rose, its pink-tipped petals curving and growing; a giant sea anemone dancing in the currents. Ancient peoples thought this is where souls were taken to the beyond. It was easy for modern ones to imagine that it might be so.