The Sentinel-3 satellite fits into the Copernicus program, a joint project between Esa and European Union. It will be dedicated to Earth monitoring and operational oceanography. This project is the European answer to the needs still growing related to the global environment.

Sentinel-3 belongs to a series of several satellites, each of which covers a different aspect of Earth Observation and monitoring. Sentinel-1 is a SAR-dedicated satellite, Sentinel-2 is an optical one, etc.