RELEASE: 04-94AR
NASA INFRARED IMAGES MAY PROVIDE VOLCANO CLUES
NASA scientists took infrared (IR) digital images of Mount Saint Helens last week. The images revealed signs of heat below the surface one day before the volcano erupted last Friday in southern Washington. The images may provide valuable clues as to how the volcano erupted.
Scientists flew an IR imaging system aboard a small Cessna Caravan aircraft over the mountain to acquire the data. "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.

"We were seeing some thermal artifacts in the floor of the Mount Saint Helens crater in southern Washington," said Bruce Coffland, a member of the Airborne Sensor Facility at NASA Ames. "We flew Thursday 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.
MASTER is an airborne simulator instrument similar to the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) high-resolution infrared imager carried on NASA's Terra Earth observation satellite. Scientists plan to fly the MASTER instrument again over the volcano early this week.

More:
NASA/AMES

http://amesnews.arc.nasa.gov/releases/2004/helen/helen.html

This is a zoomed in view of the lava dome with MASTER bands 44, 12 and 2. In this image blue indicates the snow cover, orange and yellow colors are characterizing the rock type and lava age, and the red color is indicating heat.: