The Klyuchevskaya Volcano is the highest volcano on northeastern Russia’s Kamchatka Peninsula. The 4,750-meter (15, 584-foot) peak is also the peninsula’s most active. A new phase of eruptive activity began in January 2005, with seismic activity higher than normal and repeated ash and steam plumes. On February 21, the Kamchatkan Volcanic Eruption Response Team reported that an eruption of Klyuchevskaya had produced a lava flow down the northern flank of the volcano that melted a large portion of the Ehrman Glacier, the largest of several small glaciers capping the summit and flanks of the volcano.

This image of Klyuchevskaya and neighboring volcanoes was captured by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite on February 24, 2004. ASTER’s observations from the infrared part of the electromagnetic spectrum have been added to the image to highlight the heat given off by the lava flow, which appears to glow. The snow-covered slopes of the mountain are light blue.

The large, pink-tinged plume stretching across the center and northeast part of the scene may be cloud mixed with volcanic emissions. The plume hides much of the summit crater, and it casts a wide shadow onto the terrain to the west. Just above image center, a more discrete plume of what is probably smoke, steam, and ash mushrooms above the summit. Within the shadowed area a dark line cuts down the northern slope of the volcano. The line is likely the path of the lava flow and resulting meltwater from the Ehrman glacier.

NASA image created by Jesse Allen, Earth Observatory, using data provided courtesy of NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team.