ESA is developing a new family of missions called the Sentinel for the operational needs of the Copernicus program.

Each Sentinel mission is based on a constellation of two satellites to meet coverage requirements, collecting data sets for Copernicus services. These missions carry a range of technologies, such as radar and multi-spectral instruments for tracking land, ocean and atmosphere. Sentinel-1 is a day-and-night radar survey mission for land and ocean services. Sentinel-1A was launched on April 3, 2014, and Sentinel-1B on April 25, 2016. Both satellites were launched into orbit by the Soyuz rocket from the spaceport in French Guiana.

Sentinel-2 is a multispectral high-resolution imaging mission that orbits the polar to track land. The mission provides, for example, images of vegetation, soil and water cover, inland waterways and coastal areas. Sentinel-2 can also provide information for emergency services. Sentinel-2A was launched on June 23, 2015, and Sentinel-2B on March 7, 2017. Sentinel-3 is a multi-instrument mission to measure sea surface topography, sea and land temperature, ocean color, and land color with superior precision and reliability.

The mission will support ocean forecasting systems as well as environmental and climate monitoring. The Sentinel-3A was launched on February 16, 2016, and the Sentinel-3B joined its twin in orbit on April 25, 2018. Sentinel-5 The precursor – also known as Sentinel-5P – is the forerunner of Sentinel-5 which provides timely data on a multitude of trace gases and aerosols that affect air quality and climate. It was developed to reduce the data gap between the Envisat satellite – especially the Scimaky instrument – and the launch of Sentinel-5.

The Sentinel-5P was launched into orbit by the Rockot launch vehicle from the Plesetsk cosmodrome in northern Russia on October 13, 2017. Sentinel-4 is dedicated to monitoring the atmosphere that will be placed on the Meteosat satellite of the third generation-sounders (MTG-S) in geostationary orbit. Sentinel-5 is a satellite that will monitor the atmosphere from polar orbit on a second-generation MetOp satellite. The Sentinel-6 carries a radar altimeter to measure global sea level altitude, primarily for operational oceanography and for climate studies. Looking to the future, six high-priority candidate missions are being studied to address EU policies and gaps in the needs of Copernicus beneficiaries, and to expand the current capabilities of the Copernicus spatial component.