In October 2016, the Khurdopin Glacier in Pakistan began a rapid surge after 20 years of little movement. By March, 2017, a large lake had formed in the Shimshal River, where the glacier had formed a dam. Fortunately, the river carved an outlet through the glacier before the lake could empty catastrophically. In this pair of ASTER images, acquired August 20, 2015 and May 21, 2017, the advance of the Khurdopin Glacier (dark gray and white "river" in lower right quarter of image) is obvious by comparing the before and after images. The images cover an area of 25 by 27.8 km, and are located at 36.3 degrees north, 75.5 degrees east.
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 images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched Dec. 18, 1999, on Terra. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and data products.
The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping and monitoring of 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.
The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate, Washington, D.C.
More information about ASTER is available at http://asterweb.jpl.nasa.gov/.