A puff of ash above Batu Tara, a volcano on the tiny Indonesian island of Pulau Komba, is an example of the frequent, mild eruptions that have occurred there since mid 2006. This type of activity, called Strombolian, is named after the volcanic island of Stromboli, off the coast of Italy.
The most prominent feature on Batu Tara is a scarp that drops almost directly from the 748-meter (2,454-foot) summit to the ocean. The scarp is kept clear of vegetation by frequent eruptions of rocks and ash—often incandescent—that scour the steep slope. Fresh deposits are dark gray, while exposed volcanic rock is lighter gray and vegetation is green. The Advanced Land Imager (ALI) aboard the Earth Observing-1 (EO-1) satellite captured the volcano in action on August 15, 2012.
NASA image By Jesse Allen and Robert Simmon using EO-1 ALI data. Caption by Robert Simmon.