For the last decade, Gretel Ehrlich has been obsessed by an island, a terrain, a culture, and the men and women who long for and love the complex frailties and treacherous beauty of a world defined by ice. Greenland, the world’s largest island, 840,000 square miles in extent, is covered by the largest continental ice sheet in the world. Only the rocky fringe of its coast is habitable. There, the Inuit, the Arctic’s first explorers, have survived and thrived in the harshest of climates. For the Inuit, an ice-age, ice-adapted people who first traveled from Siberia across the polar North six thousand years ago, weather is consciousness. In a world composed of ice and darkness, water and light, where skins of dog, seal, bear, even hare and eider duck, are sewn into clothes, tents, and sleeping bags as protection, where transport is by dogsled and kayak, the only rein for the uncontrollable force of weather is an unbending self-discipline. The blend of physical endurance and psychological perseverance required for daily existence first drew Ehrlich to this terrain. Her guide, her inspiration, her companion in spirit was the great Danish-Inuit explorer and ethnographer Knud Rasmussen. Between 1902 and his death in 1933 he launched seven expeditions: to record the unknown history and customs of the nomadic Eskimos; to chronicle the skills, beliefs,and crafts that made life in this climate possible and a matter of grace. For Rasmussen, “all true wisdom is only to be found far from the dwellings of man, in great solitudes.” As she followed his trail, Ehrlich was to find the things that can open the mind to what is hidden from others. This Cold Heaven is at once a distillation of her many journeys, a path into a world divided into darkness and light and, finally, an attempt to capture the clarity that blinds us with surprise.