Because of its strategic position, the City of Luxembourg was, from the 16th century until 1867, when its walls were dismantled, one of Europe's greatest fortified sites. It was repeatedly fortified as it passed from one great European power to another: the Holy Roman Emperors, the House of Burgundy, the Habsburgs, the French and Spanish kings, and finally the Prussians. Today, with a population of about 90,000, the city is the capital of the Grand Duchy of Luxembourg. The image was acquired September 21, 2006, covers an area of 10.6 x 16.5 km, and is located at 49.6 degrees north latitude, 6.1 degrees east 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/.