STS081-728-085 Lago (Lake) Nahuel Huapi, Argentina January 1997 The elongate, dark feature in the center of the image, Lago Nahuel Huapi, is a glacially formed lake in the Andes Mountains of western Argentina. The Andes cross the middle of the view; roughly the upper third of the image is of Chile and the lower two-thirds is of west-central Argentina. While the difference is subtle, note that clouds cover the mountainous terrain on the Chile side of the continental divide, while the higher elevations of the Andes in Argentina lack clouds. Lago Traful, a much smaller Argentine glacial lake, can be seen north of Lago Nahuel Huapi. An extensive watershed that includes the Rio Limay (dark feature near center bottom) can be discriminated where runoff from the Andes Mountains has created a recognizable drainage pattern in this part of the Patagonia Plateau. Numerous lakes are visible on the Chilean side of the Andes Mountains.