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NASA Infrared Images May Provide Clues About Mt. St. Helens' Eruption
One day before Mt. St. Helens erupted Oct. 1, in southern Washington, NASA scientists took infrared (IR) digital images that revealed signs of heat below the mountain's surface.

The images may provide valuable clues as to how the volcano erupted. Scientists flew an infrared imaging system aboard a small Cessna Caravan aircraft over the mountain to acquire the IR data.

Mt. St. Helens, volcano, infrared"Based on the IR signal, the team predicted an imminent eruption," said Steve Hipskind, acting chief of the Earth Science Division at NASA Ames Research Center, located in California's Silicon Valley.

Image left: In this color composite, blue indicates the snow cover, orange and yellow colors are characterizing the rock type and lava age, and the red color is indicating heat. North is at the top of the photo. Photo credit: NASA

"We were seeing some thermal artifacts in the floor of the Mt. St. Helens crater in southern Washington," said Bruce Coffland, a member of the Airborne Sensor Facility at NASA Ames. "We flew Thursday (Sept. 30) and used the 50-channel MODIS/ASTER Airborne Simulator (MASTER) digital imaging system. We are working to create images from the IR data that depict the thermal signatures on the dome," Coffland added just after the data was acquired.

MASTER is an airborne simulator instrument similar to the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) high-resolution infrared imager carried on the Terra Earth observation satellite.

The NASA Ames airborne sensor team was in the Mt. St. Helens area taking data for a United States Geological Survey (USGS) study that was looking at some of the effects of the 1980 Mt. St. Helens eruption.

"This had been planned for some time, and we were there totally by coincidence," said Coffland. The science objectives for the USGS study included outlining the boundaries of lava flows associated with Mt. St. Helens' previous eruptions in 1980.

"We flew four flight lines over the mountain," Coffland said. "It's a continuous scan image, eight miles (13 kilometers) long and about 2.3 miles (3.7 kilometers) wide," Coffland said. There were four adjoining flight lines flown for Joel Robinson, an investigator at USGS, Menlo Park, Calif.

After the plane landed, technicians downloaded data from a computer hard drive, and began to process the data to produce an image format for use by scientists.

Sky Research, based in Ashland, Ore., provided the Cessna Caravan, a propeller-driven, single-engine airplane that carried the IR imager.

More Images are available at: http://amesnews.arc.nasa.gov/releases/2004/helen/helen.html and http://masterweb.jpl.nasa.gov.

John Bluck, NASA Ames Research Center