English: The rugged and remote archipelago of Vanuatu consists of 83 islands clustered in the South Pacific Ocean, roughly 1,200 miles (2,000 km) east of Australia and 1,000 miles north of New Zealand. The islands are volcanic in origin, with many still active, including Ambae, Ambrym, Lopevi, and Yasur. Ambae is known not only for frequent activity, but also for spectacular lava lakes. Yasur volcano, on Tanna Island, stays in near-constant, low-level eruption. Along with lava and ash, volcanoes often emit steam and gas into the atmosphere. At times, volcanic fog, also known as “vog” can cover the skies near actively erupting volcanoes.

The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite acquired a true-color image of vog and cloud over Vanuatu on October 29, 2017. While no specific source can be seen, the likely culprit is Ambae, which was actively erupting as of early in the morning of October 29.

The long island in the cloud-free section of the image is New Caledonia. The red hotspots on the island mark areas where the thermal bands on the MODIS instrument detected temperatures higher than background. While such hotspots can be caused by a number of reasons, such as volcanic lava, in this case the hotspots are accompanied by smoke typical of fire. Media reports confirm a number of bushfires burning in New Caledonia in late October, 2017.