The Ambrym volcano, located in central Vanuatu, continued its simmering eruption in mid-April, 2013. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite captured this true-color image on April 18 at 2:55 UTC (1:55 p.m. local time).
The islands of Vanuatu are located in the lower right corner of the image. The green island of Espiritu Santo peeks out from under the clouds in the north, with Malekula to the south. A red “hot spot” can be seen on Ambrym Island to the east, and marks the steaming caldera of the volcano, where at lava lakes remain active – and hot. A long trail of vog can be seen stretching to the northwest over the Coral Sea, extending south and west of the Solomon Islands.
Vog is a combination of the words "volcanic" and "smog." Vog is a mix of gases and aerosols that form when sulfur dioxide and other gases from an erupting volcano reacts with sunlight, oxygen and moisture.