Planchón-Peteroa Volcano emitted a dark gray plume of ash on September 21, 2010, continuing an eruption which began on September 6th and intensified on September 18th. Planchón-Peteroa is on the border between Chile and Argentina, and the majority of the ash is blowing southeast into Argentina. Argentine authorities warned residents in the community of Malargüe—94 kilometers (58 miles) east—to be prepared in case the eruption strengthened further.
This natural-color satellite image was acquired on September 21, 2010, by the Advanced Land Imager (ALI) aboard Earth Observing-1 (EO-1). The dark ash plume rises from Peteroa, the active crater in the Planchón-Peteroa volcanic complex. An aqua-colored acid lake is just to the northeast of Peteroa. Most of the surrounding high-altitude landscape is covered in snow, some bright white, some darkened by ash. Valleys and north-facing slopes are snow free, revealing bare brown rocks.
NASA Earth Observatory image by Robert Simmon, using ALI data from the NASA EO-1 team. Caption by Robert Simmon.