This Advanced Spaceborne Thermal Emission and Reflection Radiometer
(ASTER) image of Mount St. Helens was captured one week after the March
8, 2005, ash and steam eruption, the latest activity since the volcano's
reawakening in September 2004. The new lava dome in the southeast part of
the crater is clearly visible, highlighted by red areas where ASTER's
infrared channels detected hot spots from incandescent lava. The new lava
dome is 155 meters (500 feet) higher than the old lava dome, and still
growing.
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.
Size: 21.9 by 24.4 kilometers (13.6 by 15.1 miles)
Location: 46.2 degrees North latitude, 122.2 degrees West longitude
Orientation: North at top
Image Data: ASTER bands 8, 3, and 1
Original Data Resolution: 15 meters (49.2 feet)
Dates Acquired: March 15, 2005