NASA MODIS Image of the Day: September 2, 2012 – Plume from Mount Hodson, Visokoi Island, South Sandwich Islands
In late August 2012, a large volcanic plume rose from the Mount Hodson volcano on remote Visokoi Island, interacting with clouds overhead to create a broad rippling band easily visible from space. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite captured this true-color image on August 28. The plume from Mount Hodson can be seen rising just to the northwest of center and curving in an arc to the northeast. Gas and aerosols – tiny particles of solids and liquids – emitted at a low level can provide a nucleus for the formation of water droplets, and then clouds. The area disturbed by the plume appears brighter than the surrounding clouds. This is a result of the highly reflective nature of the numerous small-sized aerosol particles emitted from the volcano, and the numerous small water droplets formed around them. Visokoi Island is located in the northern section of the South Sandwich Island chain, 47 kilometers southeast of Zadovdski Island. Measuring about 6 km by 8 km, the island consists of a single stratovolcano with a rounded, 1005 meter high summit. Historically plumes were reported above Mount Hodson in 1830 and 1930, but the Smithsonian National Museum of Natural History’s Global Volcanism Program reports that the summit is usually obscured by “smoke” or steam.
