Papua New Guinea

Although Bouganville Island is geographically part of the Solomon Islands chain, politically, the island is part of Papua New Guinea. Bouganville is typical of many Pacific Rim islands in that volcanism has played a large part in both its geological and recorded history. The island hosts three large volcanoes along its northwest-southeast trending axis: Mount Balbi, Mount Bagana, and the Mount Takuan volcanic complex. Mount Bagana, located near image center in this astronaut photograph, is the only historically active volcano on the island. Within Bouganville's lush landscape, light green vegetation and brown lava flows mark the 1,750-meter-high lava cone of Mount Bagana. The lighter color of vegetation could result from volcanic activity, higher altitude, or both. The eruptive style of the volcano is typically non-explosive, producing thick lobes of lava that run down the flanks and maintain a dome in the summit crater. Occasional pyroclastic flows of rock fragments and volcanic ash have also occurred. This image shows a diffuse white vapor plume extending west-southwest from the summit. Photo courtesy of NASA.

Numerous volcanoes contribute to the landmass of the island of New Britain, the largest in the Bismarck Archipelago of Papua New Guinea. One of the most active of these volcanoes - Ulawun - is also the tallest, with a summit elevation of 2,334 m (7,657 ft). This astronaut photograph shows a plume of white steam and ash extending from the summit crater of the stratovolcano towards the northwest. The plume begins to broaden as it passes the southwestern coast of Lolobau Island, approximately 23 km downwind. Note that north is towards the lower left. Ulawun is also known as "the Father," with the Bamus volcano to the southwest also known as "the South Son." The summit of Bamus is obscured by white cumulus clouds (not of volcanic origin) in this image. While Ulawun has been active since at least 1700, the most recent activity at Bamus occurred in the late 19th century. A large region of ocean surface highlighted by sunglint - sunlight reflecting off the water surface - is visible to the north-northeast of Ulawun. Photo courtesy of NASA.

Volcanic cones and settlements mingle along the margins of the Rabaul Caldera on the northeastern tip of Papua New Guinea's New Britain Island. Shaped like a giant cauldron, the caldera is the remaining rim of an ancient volcano. Small volcanic cones, some of which are still active, sit on the rim. Spanning roughly 8 by 14 km (5 by 9 mi), the caldera is flooded by Blanche Bay. The largely submerged caldera long formed a natural harbor for what had been New Britain's largest city, but a major eruption forced the evacuation of Rabaul City in 1994. Although the city ceased to bustle with activity, at least one volcanic cone remained active for years afterward. The landscape in this satellite image appears as a mixture of vegetated and bare ground. Vegetation almost completely coats the western side of Rabaul Caldera. Volcanic cones line the northeastern margin of the caldera, and around these cones, the land is mostly rocky and barren. Tavurvur, near the southern end of the exposed caldera rim, was one of the volcanoes to erupt explosively in 1994. The other was Vulcan, on the western side of the caldera. While vegetation has revived on the slopes of Vulcan, rocks predominate at Tavurvur, evidence of more recent eruptive activity. Remnants of settlements linger along the caldera's northwestern margin and on a promontory near the caldera's center. Prior to the explosive eruption in 1994, the city of Rabaul had been the provincial capital of East New Britain. After the eruption, the capital was moved to the coastal city of Kokopo, some 20 km (12 mi) to the southeast. Photo courtesy of NASA.

Satellite view of the western Pacific Ocean and the South China Sea shows the location of the Spratly Islands between Vietnam and the Philippines. Image courtesy of NASA.

NASA's Terra satellite captured this image of "the troublesome trio" on Papua New Guinea's New Britain island when they erupted simultaneously on 9 August 2005. Langila, Ulawun, and Rabaul Volcanoes all spewed ash at the same time, though not all with the same results. The westernmost volcano, Langila, and the easternmost volcano, Rabaul, sent fairly faint plumes of ash into the air, both of which drifted toward the northwest. Ulawun, the most active volcano in this picture, spit out a dense stream of ash that flew straight south. The volcanoes' proximity to each other and propensity for acting up at the same time suggest that they could be affected by the same tectonic activity underground. Photo courtesy of NASA.

As part of a multinational training exercise, US Marines and US Sailors, Australian soldiers, and British soldiers hike a hill along the Kokoda Track in Papua New Guinea in 2015. The exercise was designed to provide assistance to Papua New Guinea through infrastructure rehabilitation and basic military training. Photo courtesy of the US Marine Corps/ Cpl. William Hester.