The SeaWiFS (Sea-viewing Wide Field-of-view Sensor) instrument placed in orbit in 1997 uses just such an approach, scanning 8 wavelength bands strategically located between 402 and 885nm of the electromagnetic spectrum and using the data to infer ocean color properties. This instrument, carried by the OrbView-2 (AKA SeaStar) satellite, is in constant low Earth orbit such that it provides images representing complete coverage of the surface every 48 hours. The image below shows how a phytoplankton bloom looks from space to the human eye, as captured by SeaWiFS.