| A L P H A C E N T A U R I P L A N E T A R I U M |
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This east-looking, high-oblique
photograph features Lake Tanganyika—the second
deepest freshwater lake in the world with a maximum depth
of 4710 feet (1436 meters) and the longest lake in the
world, stretching 410 miles (660 kilometers) north to
south. Its width varies between 10 and 45 miles (16 and
72 kilometers). The lake, bordered on either side by
steep slopes, fills a long narrow trough in the western
arm of Africa’s Great Rift Valley and supports a
thriving fishing industry. The lake basin, a landform in
which a block of the Earth’s crust dropped down
between blocks that rise on either side, began to form
nearly 25 million years ago as part of the Great Rift
Valley. On the lake’s west shore is Tanganyika’s
sole outlet, the Lukuga River, which is a tributary of
the Zaire River (northwest portion of photograph). The
Zaire River flows westward and empties into the Atlantic
Ocean. Other features in the photograph are shallow, silt-laden
Lake Rukwa to the east of the lake and the extreme
northern tip of Lake Nyasa near the southeast horizon. |
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E X P L O R A T I O N O F T H E E A R T H A N D M O O N |