Batu Tara volcano ash plumes. Footage of the coast of the Batu Tara volcano, looking up towards the main crater. Batu Tara forms the island of Komba which lies around 50 kilometres off the north coast of Lembata Island, one of the Lesser Sunda Islands of Indonesia. This stratovolcano is the most north-easterly of the Flores-Pantar sector of the Sunda Arc. The most recent activity began in 2006. The volcano generally erupts explosively from a central vent near the top of an eastward-oriented collapse feature.