Byrd Glacier is a major glacier in Antarctica. About 135 kilometers (84 miles) long and 24 kilometers (15 miles) wide, it drains an extensive area of the polar plateau and flows eastward between the Britannia Range and the Churchill Mountains to discharge into the Ross Ice Shelf. This image was created with data from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on NASA's Terra satellite.

Using data from ASTER, along with data from other NASA satellites, the Japanese Advanced Land Observing Satellite and the French SPOT satellite, researchers at the universities of Maine and Washington recently discovered a year-long increase in the flow speed of the glacier due to sub-glacial floods and drainage of two large sub-glacial lakes. Scientists want to know more about the processes that control the speed of such glaciers. Should they happen at larger scales, they could cause sea level to rise more rapidly.

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 December 18, 1999, on NASA's Terra satellite. 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 the 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.

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

Size: 40 by 80 kilometers (24.8 by 49.6 miles)
Location: 80.3 degrees South latitude, 159 degrees East longitude
Orientation: East at top
Image Data: ASTER Bands 3, 2, and 1
Original Data Resolution: 15 meters (49.2 feet)
Date Acquired: December 12, 2007