Vega-C fairing opens to reveal Sentinel-3C and FLEX

Sentinel-3C and FLEX are launched together on a Vega-C rocket. Sentinel-3C is injected into orbit first so it sits above FLEX in the Vega-C fairing. To accommodate the two satellites in the fairing, FLEX is encapsulated within the lower part of a secondary payload adapter called Vespa.

FLEX is designed to reveal a phenomenon invisible to the human eye: the faint fluorescence emitted by plants as they photosynthesise. Equipped with a Fluorescence Imaging Spectrometer, FLEX will detect and measure this incredibly weak signal from orbit. Because the fluorescence varies with plant health and environmental conditions, the measurements will provide scientists with new information about photosynthetic activity and vegetation stress on a global scale.

Sentinel-3C is the third satellite in the Copernicus Sentinel-3 series. Like its two older siblings in orbit, Sentinel-3C carries a suite of cutting-edge instruments that measure systematically Earth’s oceans, land, ice and atmosphere to monitor and understand large-scale global dynamics. It provides essential information in near-real time for ocean and weather forecasting.