Aletsch Glacier, Switzerland
© Science & Society
Aletsch Glacier, the largest glacier of Europe, covers more than 120 square kilometers (more than 45 square miles)in southern Switzerland. At its eastern extremity lies a glacierlake, Mdrjelensee (2,350 meters/7,711 feet above sea level). To the west rises Aletschhorn (4,195 meters/13,763 feet). The Rhone River flows along the southern flank of the mountains. This image was acquired on July 23, 2001 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet. The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.