WATERLOO - It was Feb. 11 when 2nd Lt. Donny Heaton and a couple of dozen friends gathered on a high point to greet the sun.

For four months in northern Greenland they had lived without a hint of natural light.

And they'd live without it once again, as clouds obscured the sun.

Two days later, the "first light" finally came.

The Waterloo native returned earlier this month from a one-year stint at Thule Air Force Base, where he experienced months of 24-hour days and 24-hour nights.

Through the winter he endured stretches for months at a time when temperatures were between 20 and 30 below zero. When a severe winter storm would pick up, people wouldn't be allowed to leave the building they were in.

Following graduation from the Air Force Academy and training near sunny San Diego, Heaton volunteered for the arctic expedition.

"I really enjoyed it. I'd go back another year. The people are great," Heaton said. "You create strong bonds, because everywhere you go it's the same people."

During the long, hard winter, Heaton kept himself occupied by working out at the gym on base and playing floor hockey. An Air Force-issued sun lamp helped him deal with the lack of light.

The four months of 24-hour sunlight offered more opportunities to explore the tundra.

Thule is isolated, the nearest human settlement being an Inuit village 65 miles away. Once a year, the villagers come to the base. Heaton took advantage of that trip last year to join an Inuit man on a dog-sledding outing. He tried to control the 16-dog team as it skidded across the snow and ice. Then he watched as the man pulled up a trap from below the ice and produced a seal.

Heaton ran a half marathon on a wind-swept, rain-spattered 36-degree day. He climbed Mount Dundas, a rocky rise near the base.

The bay where Thule is located is free from ice only three months a year. The Air Force's only tugboat clears icebergs from the bay to let in the annual resupply ships.

Of course, the water can't be mistaken for tropical. Heaton participated in a polar bear swim, jumping into 29-degree water.

"I loved it so much I went again and again. I ended up going 11 times," he said. The longest Heaton stayed in the water was 2 minutes and 15 seconds. He did, however, once swim out to an iceberg. He brought home a photo of himself perched, in swim trunks, atop the berg.

Thule is 695 miles north of the Arctic Circle; less than 1,000 miles north lies the North Pole. When the snow melts in the summer, the landscape remains mostly barren rock. The most common wildlife on the base are arctic fox, which thrive on scavenged food from trash bins.

When Heaton arrived in Waterloo earlier this month to visit his family, it was 50 degrees warmer than it was when he left Greenland.

Now that his stint at Thule is over, Heaton has already moved on to his next assignment.

"I was hoping for somewhere warm, Hawaii or California, but I wound up with Great Falls, Mont.," Heaton said.

Contact Jon Ericson at (319) 291-1461 or jonathan.ericson@wcfcourier.com.