Scarborough’s foot party was no less appreciative of the human contact. They were starting their first full day out of Cold Corners, and if mutual reliance made for good neighbors, this qualified as the most neighborly spot on earth.

All three returned the pilot’s wave, their own bright red coat sleeves upraised. Then they watched him level his bird in the crystal-clear sky, skirt the rim of Valhalla glacier, and vanish over the crooked spine of mountains running toward the coast. Away and gone with due haste. The fixed landing and refueling pad at Marble Point was some thirty miles off along his flight path, and he’d want to reach it in time for the early shift change.

Minutes later, Scarborough could still hear the chop of rotors echoing between the scoured brown walls of the pass.

The most neighborly spot on earth, and its quietest, he thought. The polar desert’s only native inhabitants were primitive invertebrates. A handful of tiny worms and insects on land, anaerobic microbes under the hardened lake surfaces. There would be no noise pollution from them. Nothing to dent the silence except for the occasional beating of wind against the valley walls and far rarer sounds of human intrusion.

Now Scarborough freed a hand from its clumsy pile mitten, leaving on his thinner polypropylene glove liner, adequate short-term protection on all but the worst summer days. The temperature had been 16° Fahrenheit when his group left camp that morning, torrid by local standards even with a chill factor of—20°, and he would need just a few moments to check his bearings.

Scarborough extricated his GPS receiver from his parka and pressed a keypad button. A topographic satellite image of the valley system north of the Asgard range filled his display, its contours reminding him of an old-fashioned ship’s anchor. Next, he scrolled down his menu to the “Navigate” option. A color icon representing the object of his search marked its last known coordinates near the deep, craggy notch at the pass’s junction with Wright Valley.

Scarborough studied the display a bit longer, his fur-trimmed hood pulled up, his balaclava covering the gray-flecked scruff of beard that would soon grow out into a winter forest. He wore dark polarized snow goggles over the mask’s eye slits, heavy-duty wind pants, and neck and leg gaiters for optimal retention of body heat. Here at the bottom of the globe, life was bounded by the cold, shaped by the cold, its limitations defined by how well you adapted to the cold. The threat of hypothermia meant bundling into innumerable layers of gear and apparel before you ventured outside, a tedious routine that packed on thirty pounds of added weight and was the cause of persistent, some might say epidemic, crankiness at the station.