Lake St. Clair, US and Canada

Lake St. Clair connects Lake Huron, via the St. Clair River, to Lake Erie, via the Detroit River. It is named after Claire of Assisi, on whose feast day it was first navigated by French explorers in 1679. The lake covers an area of about 1100 square kilometers, with an average depth of 3.5 meters. Both the U.S. and Canada maintain a deep shipping channel through the lake. The image was acquired September 9, 2002, covers an area of 51.4 by 52.5 kilometers, and is located at 42.5 degrees north, 82.7 degrees west.

With its 14 spectral bands from the visible to the thermal infrared wavelength region and its high spatial resolution of about 50 to 300 feet (15 to 90 meters), 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 in Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate, Washington.

More information about ASTER is available at http://asterweb.jpl.nasa.gov/.