Earth Observations taken by the Expedition 17 Crew

ISS017-E-005037 (19 April 2008) --- Santorini Volcano, Greece is featured in this image photographed by an Expedition 17 crewmember on the International Space Station. According to scientists, one of the largest volcanic eruptions in the past 10,000 years occurred approximately 1620 BC on the volcanic island of Santorini in the Aegean Sea. This view illustrates the center of Santorini Volcano, located approximately 118 kilometers to the north of Crete (not shown). Prior to 1620 BC, the island of Santorini -- now known as Thera -- had been built up by layers of lava created by overlapping shield volcanoes, and had experienced three significant eruptions that formed overlapping calderas, or collapsed magma chambers. Around 1620 BC, the fourth (and latest) major eruption created the present-day islands and caldera bay of Santorini Volcano. The caldera rim is clearly visible in this image as a steep cliff forming the western shoreline of the island of Thera. Following the 1620 BC eruption, much of the previous island of Santorini was destroyed or submerged. The white rooftops of cities and towns trace the caldera rim on the island of Thera, and overlook the young central islands of Nea Kameni and Palaea Kameni -- both, according to scientists, formed from lava domes and flows that started erupting approximately 1400 years after the last major caldera-forming event. Several of these flows are visible in the image as brown to dark-brown irregular masses forming Nea Kameni (left). The most recent volcanic activity in the Kameni islands occurred in 1950, and included some small explosions and production of lava. The extent of development and location of an airport (upper right) on Thera illustrate the popularity of Santorini Volcano as a tourist destination. Today, volcanic activity is closely monitored by the Institute for the Study and Monitoring of the Santorini Volcano, or ISMOSAV.