A tan cloud of ash fans west from the Anatahan Volcano in this Moderate Resolution Imaging Spectroradiometer (MODIS) image, acquired on May 23, 2005, by the Terra satellite. The volcano has been erupting almost continuously since late March, including one massive eruption on April 6 in which it sent as much as 50 million cubic meters of ash into the atmosphere in a single day. Because ash can destroy jet engines, pilots have been warned to avoid the area immediately around the volcano, according to the current update issued by the United States Geological Survey and the Emergency Management Office for the Northern Marianas Islands.
Anatahan sits near the center of the Northern Marianas Islands. The islands are a classic island arc, created when the Pacific Plate, the slab of the Earth’s crust that carries the Pacific Ocean, collides with the Philippine Plate. The Pacific Plate sinks beneath the Philippine Plate, its rock breaking and heating under the pressure. The hot rock forces its way through weak spots in the Philippine Plate and bursts to the surface in volcanoes such as Anatahan. The arc of volcanic islands that form the Northern Marianas lines the edge of the Philippine Plate.
The MODIS Rapid Response Team provides daily images of Anatahan in a variety of resolutions, including MODIS’ maximum resolution of 250 meters per pixel.
NASA image courtesy the MODIS Rapid Response Team at NASA GSFC.
