Earth observations taken during STS-77 mission

STS077-711-012 (19-29 May 1996) --- One of several volcanic-laden photo targets for the crew members was the grouping of the Galapagos Islands -composites of flat-topped volcanoes produced by a hot spot in the eastern Pacific. Dark lava flows drape the flanks of each volcano. This view centers on Isabella, the sea horse-shaped island. The most active volcano is the island of Fernandina, which sits just west (up) from the sea horse?s middle area. Fernandina erupted late last year, and Shuttle photography has documented the changes produced by eruptions over the past 10 years. Because the Galapagos Islands sit on the equator and near the junction of current systems in the eastern Pacific Ocean, and the volcano provides a sharp topographic barrier to the currents, many interesting oceanic phenomena occur and have been recorded in this region. Lighter colored water occurs just west of Isabella and Fernandina. The origin of the color difference is unknown, but could possibly be plankton blooms related to upwelling around the islands.