Augustine Volcano, Cook Inlet, Alaska
This Jan. 31, 2006, image shows the increased activity of Augustine Volcano in Cook Inlet, Alaska near Anchorage. Such increased activity began last spring. During the last month, activity has been episodic, and characterized by emission of steam and ash plumes, rising to altitudes in excess of 9,000 meters (30,000 feet), a height which poses hazards to aircraft in the vicinity. In the last week, volcanic flows have been seen on Augustine's flanks. This image, taken by ASTER, shows three volcanic flows down the north flank of Augustine as white (hot) areas. The eruption plume spreads out to the east in a cone shape and appears dark blue over the summit because it is cold and water ice dominates the composition; further downwind a change to orange color indicates that the plume is thinning and the signal is dominated by the presence of ash.
Image Credit: NASA/GSFC/METI/ERSDAC/JAROS and U.S./Japan ASTER Science Team