An astronaut aboard the International Space Station took this photograph of solar evaporation ponds outside the city of Moab, Utah. The 23 colorful ponds spread across 400 acres are part of a large operation to mine potassium chloride—more commonly referred to as muriate of potash (MOP)—from ore buried underground. MOP is in high demand as fertilizer because there are no easy substitutes for potassium, an essential nutrient for plant growth.
Shadows cast on the landscape show the depth and dimension of the surrounding Utah desert. The Colorado Plateau stands at an average elevation of 1,600 meters (5,200 feet) above sea level, in contrast with the Colorado River Valley, with an average elevation of 1,200 meters (3,900 feet). The darker areas along the river bank are rich in green desert vegetation.