This image, captured by the Copernicus Sentinel-3 mission on Saturday, 5 September, shows a plume from the eruption of Anak Krakatau. The small volcanic island, in the Indonesian archipelago situated between Sumatra and Java, began spewing ash and lava on 4 September. This caused disruption and flight cancellations at Jakarta’s Soekarno-Hatta International Airport over the weekend, although the airport has now reopened.
In this image, the white plume is a mix of volcanic gases that have reached a high altitude – gases emitted during eruptions usually consist mainly of water vapour, carbon dioxide and sulphur dioxide. The brown clouds also seen in the image are made up of ash and debris drifting at a lower altitude.
The image was captured by Sentinel-3’s Ocean and Land Colour Instrument (OLCI), an imaging spectrometer. This optical instrument has 21 distinct spectral bands that measure data on ocean colour and vegetation with a spatial resolution of 300 m. This provides data for monitoring ocean ecosystems, supporting crop management and agriculture and providing estimates of atmospheric aerosol and clouds.
The Copernicus Sentinel-3 mission consists of two satellites, with a third satellite due to launch on board a Vega-C launcher from Europe’s Spaceport in French Guiana on 15 September (03.21 CEST, 22:21 local time on 14 September).