Der FLEX-Earth-Explorer-Satellit der Europäischen Weltraumorganisation und der Copernicus-Sentinel-3C-Satellit wurden gemeinsam an Bord einer Vega-C-Rakete vom europäischen Weltraumbahnhof in Französisch-Guayana aus gestartet und markieren damit einen neuen Meilenstein in den europäischen Erdbeobachtungsprogrammen.

Zwei Erdbeobachtungssatelliten – der „Fluorescence Explorer“ (FLEX) der ESA und der dritte Satellit der Copernicus-Sentinel-3-Mission – befinden sich in der Nasenkonuskapsel einer Vega-C-Trägerrakete und warten im europäischen Weltraumbahnhof in Französisch-Guayana auf den Start.

On 15 September, two spacecraft will leave Earth together aboard the same launcher from Europe’s spaceport in Kourou: FLEX, ESA’s photosynthesis mission, and Sentinel-3C, Copernicus’ newest satellite monitoring Earth’s oceans, land, ice and atmosphere.At ESA’s European Space Operations Centre (ESOC), two independent mission teams are preparing to operate the spacecraft in parallel in a closely coordinated effort. As launch approaches, they are rehearsing side by side to prepare not only for their own missions, but also for the moments when the two operations intersect.

If you had to describe a plant, the first thing you might start with is its colour – and the first colour that usually comes to mind, is green. And indeed, by and large, plants appear green to our eyes because they contain chlorophyll, which absorbs blue and red light much more strongly than green light. Behind this green façade though, plants are secretly glowing. This phenomenon is called solar induced fluorescence, and it gives scientists an unusual way to spy on photosynthesis – all the way from space.As ESA prepares to launch its Fluorescence Explorer (FLEX) mission on 15 September 2026, here are 10 surprising facts about this faint glow that could transform how we assess the health of Earth's vegetation.

Sentinel-3C ontop of the Vespa adapter which encases FLEX

FLEX and Sentinel-3C atop Vega-C

Alexandra Lora, Spacecraft Operations Engineer for ESA’s FLEX mission

Isabelle Dauvin, a Spacecraft Operations Manager for ESA’s FLEX mission