Large plumes of smoke and ash filled the Indonesian sky as Mount Semeru, in East Java, erupted on August 14. Standing 12,057 feet tall, Semeru is the tallest – and one of the most active – volcanoes on Java Island. Since 1967, Semeru has been in an almost constant state of eruption, according to the global volcanism program run by the Smithsonian Institution.Travel vlogger Ryan Purvis caught the dramatic eruption on camera, seen in this video from several angles. Credit: YouTube/Ryan Purvis