On Sunday, October 26, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) captured this image of the Old Fire/Grand Prix fire burning on either side of Interstate 15 near the Cajon Pass in the San Bernardino Mountains, roughly 80 km (50 mi) east of Los Angeles, CA. When this image was acquired, the fire had burned more than 80,000 acres, consumed 450 structures, and caused 2 fatalities. Most of the local communities were evacuated as the fire continued to spread rapidly, fanned by the intense Santa Ana winds.
The top image in simulated natural color shows the how the scene would look from above to a human eye, while the bottom image combines ASTER bands 4, 3, and 1 to produce a thermal infrared look at the scene. Notice how much more detail on the surface is apparent in the bottom image—the bright red-orange ribbon snaking along the northern side of the burn is the actively burning fire front, while the darker crimson patch shows the smoldering burn scar. ASTER is one of five instruments aboard NASA’s Terra satellite.
(Note, the high-resolution copy of the thermal infrared image available here is 55 x 45 km, and the high-res version of the simulated natural color image covers an area of 83 x 54 km).