In the Bhutan Himalayas, Advanced Spaceborne Thermal Emission and
Reflection Radiometer data have revealed significant spatial variability
in glacier flow, such that the glacier velocities in the end zones on the
south side exhibit significantly lower velocities (9 to 18 meters, or 30
to60 feet per year), versus much higher flow velocities on the north side
(18 to 183 meters, or 60 to600 feet per year). The higher velocity for the
northern glaciers suggests that the southern glaciers have substantially
stagnated ice. This view looking towards the northwest was created by
draping an ASTER simulated natural color image over digital topography
from the ASTER Global Digital Elevation Model (GDEM) data set. The ASTER
scene was acquired November 20, 2001, and is centered near 28.3 degrees
north latitude, 90.1 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 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/.