FLEX and Sentinel-3C share a Vega-C ride from Kourou
Flight VV30 put an Earth-observation research craft and an operational Copernicus satellite into orbit on 15 September.
A Vega-C lifted off from Europe’s Spaceport in French Guiana at 03:21 CEST on 15 September 2026 (22:21 local time on the 14th). Flight VV30 carried two satellites. A stack adapter called Vespa let Sentinel-3C ride on top and leave first. FLEX followed about an hour later. ESOC in Darmstadt had a first signal from each after separation.
FLEX, short for Fluorescence Explorer, is an Earth Explorer research mission. Its spectrometer is built to catch the faint glow plants give off while they photosynthesise. That glow is a more direct read on plant health than inferring it from colour alone. Sentinel-3C is the third satellite in an operational series. It continues measurements of ocean and land temperature, ocean colour, sea and ice, vegetation, and inland water. After commissioning, Eumetsat runs Sentinel-3C day to day. FLEX stays with ESA.
The two are meant to work as a pair later on. FLEX will first fly in tandem with Sentinel-3A. Sentinel-3C is then due to take that tandem slot, so the fluorescence measurement can be read next to a near-simultaneous view of cloud, aerosol, surface temperature, and land cover.
One rocket, two jobs. That is the useful part of the manifest: a research instrument and a data service, stacked, with different owners after they reach orbit.
Desk note from a public release. Source: ESA. This site is not the agency.