The SENTINEL-2 MSI observation scenario implements a pre-defined SENTINEL High Level Observation Plan (HLOP), and is focused on delivering the observation requirements for the Copernicus services. The SENTINEL HLOP can be found here.
For more information on the mission coverage please visit the Revisit and Coverage section of the User Guide.
The SENTINEL-2 mission systematically acquires data over land and coastal areas in a band of latitude extending from 56° South (Isla Hornos, Cape Horn, South America) to 82.8° North (above Greenland):
- all coastal waters up to 20 km from the shore
- all islands greater than 100 km2
- all EU islands
- the Mediterranean Sea
- all closed seas (e.g. Caspian Sea).
In addition, the SENTINEL-2 observation scenario includes observations following member States or Copernicus Services requests (e.g. Antarctica, Baffin Bay).
In addition to the nominal acquisition mode, and in order to maintain the performance of the instrument during the mission lifetime, at regular intervals throughout the Mission the instrument is placed in one of two Calibration modes:
- Dark signal calibration: image acquisition when the instrument is traversing the eclipse (dark) phase of the orbit. Dark signal calibration data are acquired more precisely over Pacific or Atlantic Ocean (except nearby South Atlantic anomaly) in ascending orbit. Possible areas are in the neighbourhood of position long. 120°W, lat. 0°. Neighbourhood can easily be +/-10° in both longitude and latitude. Generally, these dark images are acquired twice / month.
- Sun signal calibration: SENTINEL-2 MSI acquires the signal coming from the on-board reference diffuser illuminated by the sun. The calibration mode is operated over the North Pole, as the satellite is there adequately exposed to the solar beam. The satellite does not perform any specific manoeuvre during the calibration and is still pointing towards Earth. The shutter is moved to the calibration position right before the solar beam reaches the appropriate incidence (baseline is 60°). The acquisition is then performed for all channels during an appropriate time (at least 8 seconds) allowing an averaging of noise. Afterwards the shutter is moved to position opened. This calibration mode is used for both the absolute and the relative gains calibrations. Sun signal acquisitions occur once / month.