English: The paradise-like Vanuatu archipelago sits in the South Pacific Ocean, about three-quarters of the way from Hawaii to Australia. Comprised of more than 80 islands, about 65 of which are inhabited, the spectacular scenery includes forests, waterfalls, villages, towns, beaches, and the ever-present heart of the archipelago – volcanic mountains.

The islands were created by volcanic activity and are part of the famous “ring of fire” – a string of volcanoes and sites of seismic activity that encircles the edges of the Pacific Ocean. According to National Geographic, roughly 90% of all earthquakes occur along the Ring of Fire and the ring is dotted with 75% of all active volcanoes on Earth. Vanuatu is home to some of the most active volcanoes in the world, including the near-constantly erupting Yasur volcano on the island of Tanna and the bubbling lava lakes of Ambrym.

In late September 2017, intense rumblings of the volcano on Aoba Island forced the evacuation of more than 8,000 inhabitants. Aoba Island (also known as Ambae) is made up of a broad pyroclastic, Hawaiian-style shield volcano with nested calderas. On September 23 the volcanic alert for the island’s major volcano was raised to 4, the second-highest level on a five-step scale after activity at the volcano started to increase. The eruption, classified as “moderate” put many people on the island at risk, particularly to the north and south of the summit and areas near or in valleys draining from the caldera lake. According to Reliefweb, it is expected that flying rocks and volcanic gas will affect about 6.5 km radius around the caldera, and ash fall and acid rain may cause difficulties, especially to crops. The government has been evacuating citizens from the high-risk areas on the island. In 2005, similar high activity required an evacuation and people were not able to return for 3 months.

On September 29, 2017, the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite acquired a true-color image of volcanic activity in Vanuatu. Red hot spots mark areas where the thermal bands on the instruments detected high ground temperatures. In this case, the heat is caused by heat emitted by volcanic eruption or lava lakes, fields, or flow. The active volcanoes seen in this image are, from the north to the south are Aoba (Ambae), Ambrym, and Lopevi. Both Aoba and Ambrym are marked by large hot spots. Lopevi, which is located on a small island just southeast of Ambrym, does not show a hotspot but a thin ash plume is visible.