This true-color satellite image of lower South America shows the Andes along the left-hand side, starting out wide up top and narrowing as they move south. The white spine-like strip along the lower Andes is snow. Mount Aconcagua, the tallest mountain in the Western Hemisphere, is located in this section of the Andes. To the east, the muddy green featureless areas in the image are the vast wetlands of Paraguay (further north) and Argentina (in the south). The largest lake in this region is Lake Mar Chiquita, which sits on the western edge of these wetlands. The two whitish tan patches between the lake and the Andes are the much smaller, snow-covered Sierra de Cordoba mountains. Photo courtesy of NASA.