On May 14, 2011, the U.S. Army Corps of Engineers opened the Morganza Spillway, a flood control structure along the western bank of the Mississippi River in Louisiana, to ease flooding along levee systems further downstream in heavily populated regions, including New Orleans. The 3,900-foot-long (1,200-meter-long) spillway, completed in 1954, includes 125 gated openings that can allow up to 600,000 cubic feet (17,000 cubic meters) of water per second to be diverted from the Mississippi River into the Atchafalaya Basin during major flood events. As of May 18, 17 of the gates had been opened, diverting water from the Mississippi River at the rate of 114,000 cubic feet (3,230 cubic meters) per second. The region is depicted from space in this image from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on NASA's Terra spacecraft, acquired May 18, 2011. The white pixels near the spillway are churned-up water flowing through the open gates. Vegetation is green, bare fields are light brown and tan, and the water is light to dark gray and black. The image covers an area of 25.6 by 37.6 kilometers (15.9 by 22.9 miles) and is located near 30.4 degrees north latitude, 91.6 degrees west longitude.
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/.