Sentinel-2 is a multispectral, high-resolution, optical imaging mission, developed by the European Space Agency (ESA)
in the frame of the Copernicus program of the European Commission. In cooperation with ESA, the Centre National
d’Etudes Spatiales (CNES) is responsible for the image quality of the project, and will ensure the CAL/VAL
Sentinel-2 mission is devoted the operational monitoring of land and coastal areas, and will provide a continuity of
SPOT- and Landsat-type data. Sentinel-2 will also deliver information for emergency services. Launched in 2015 and
2016, there will be a constellation of 2 satellites on a polar sun-synchronous orbit, imaging systematically terrestrial
surfaces with a revisit time of 5 days, in 13 spectral bands in visible and shortwave infra-red. Therefore, multi-temporal
series of images, taken under the same viewing conditions, will be available.
This paper first briefly presents Sentinel-2 system, the design, the level-1 products, and the main geometric image quality
requirements: geolocation with and without ground control points, multi-temporal and multi-spectral registration. Then,
it presents the methods foreseen during commissioning: the viewing frames orientation, the focal plane mapping, the
global reference image generation. Finally, it presents the Sentinel-2 image simulation tool, used to provide data for the
validation of these developments.