STS028-076-054 Missouri River and Little Rocky Mountains, Montana, U.S.A. August 1989 The Missouri River, heavy with silt and bounded in many places by steep cliffs; portions of the Little Rocky Mountains, an isolated cluster of low igneous rock peaks that were uplifted through the rocks of the high Great Plains 50 million years ago; and numerous canyonlike features are visible in this southeast-looking, low-oblique photograph. This region of the river is part of the Missouri Breaks Wild and Scenic River Area. Just below the top of the photograph, Armells Creek can be seen as it enters the Missouri River.