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View of Alaska from space on a rare, cloud-free day. Snow blankets much of the land area. Trees, obscuring the snow, appear as dark areas. Picture was taken by Nimbus IV Image Dissector Camera System (scale, approximately 1 : 15,000,000). See page 4029. [National Aeronautics and Space Administration, Greenbelt, Maryland]


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Science. ISSN 0036-8075 (print), 1095-9203 (online)