The FLuorescence EXplorer (FLEX) mission will collect global chlorophyll fluorescence data from vegetation, providing clues to photosynthetic activity and plant health. This information is essential to better understand and characterize the global carbon cycle. This understanding can support developments in agriculture and contribute to food security.

That is why FLEX was selected as the eighth Earth Explorer Mission of the European Space Agency (ESA) Living Planet program in 2015 ( mission selection report). FLEX will fly in tandem with the Coperincus Sentinel-3 mission so that data from the OLCI and SLSTR instruments can contribute to the interpretation of the FLEX data.

Data about FLEX:

  • Start: 2026
  • Launcher: Vega-C
  • Mission duration: 3.5 years
  • Size: 1.5 x 1.2 x 1.2 m (LxWxH), 5.2 m wide after unfolding the solar panels
  • Satellite mass: 460 kg (of which 140 kg instruments, 30 kg fuel)
  • Orbit: sunsynchronous, at 814 km, inclination 98.64°
  • Repetition rate: 27 Tage
Flex Concept Pillars: European Space Agency
European Space Agency


The Fluorescence Imaging Spectrometer (FLORIS) is a hyperspectral line scanner in a spectral range of 500-780 nm with 0.1 nm spectral sampling in the oxygen absorption bands (759-769 and 686-697 nm) and 0.5-2 nm in the red-edge bands, of chlorophyll absorption and in the area of the photochemical reflection index (PRI).

Control segment:

ESA Space Operations Centre (ESOC) Darmstadt together with coordination of the  tandem operation with Copernicus Sentinel-3 by EUMETSAT

communication interface:

X-band scientific data Svalbard, Norway, S-band telemetry Kiruna, Sweden

Data centre:

ESA’s Centre for Earth Observation (ESRIN) Frascati, Italien