The Sea-viewing Wide Field-of-view Sensor instrument, an ocean colour scanner launched in August 1997 aboard the SeaStar satellite (the satellite was later renamed Orbview). The SeaWIFS instrument was comparable and complementary to the Medium Resolution Imaging Spectrometer (MERIS) on ESA's Envisat, and monitored subtle changes in ocean colour to identify pollution and concentrations of marine phytoplankton. The spacecraft and instrument are owned by Orbital Sciences Corporation, which markets the data for commercial use. SeaWIFS ceased operations in December 2010.