Great Sand Dune National Monument, CO, USA

STS040-151-126 (5-14 June 1991) --- Croplands of the San Luis Valley stand out exceptionally clearly from low Earth orbit. The Rio Grande flows through the valley. Circular center pivot irrigation patterns have almost completely replaced the earlier rectangular grid pattern. Pinto beans are the specialty of the area. The Great Sand Dunes National Monument appears in fine detail near the center of the picture. The sands of these dunes have been blown from the valley floor by westerly winds in the course of the last few tens of thousands of years, now banked up against the foot of the Sangre de Christo Mountains (snowcapped peaks reach over 14000 feet). The town of Alamosa lies on the Rio Grande. The San Juan Mountains appear at the bottom left.