Vega-C | Sentinel-3C & FLEX: Launch Time & How to Watch (11 Sep 2026)

When is the Vega-C launch of Sentinel-3C and FLEX?

The Vega-C rocket, operated by Italy's Avio S.p.A, is scheduled to lift off no earlier than 00:00 UTC on 11 September 2026. The mission will fly from the Ariane Launch Area 1 (ELV) at the Guiana Space Centre in Kourou, French Guiana. As with many Earth-observation launches, the status remains TBD, so the date and time may shift as launch preparations progress.

You can follow the countdown and check for schedule updates on our rocket launch schedule.

What is the payload?

This dual-payload mission carries two European Space Agency Earth-observation satellites: Sentinel-3C and FLEX.

Sentinel-3C

Sentinel-3C is part of the European Union's Copernicus programme, the world's most ambitious Earth-monitoring initiative. The Sentinel-3 series measures ocean and land surface temperature, sea-surface topography, ocean colour and land colour with high accuracy. These measurements support marine forecasting, climate monitoring, and environmental management. Sentinel-3C is designed to ensure continuity of this critical data stream as earlier satellites in the series age.

FLEX (FLuorescence EXplorer)

FLEX is an ESA Earth Explorer mission built to map vegetation fluorescence across the globe. By detecting the faint glow emitted by plants during photosynthesis, FLEX will provide unprecedented insight into the health and productivity of the world's vegetation. The mission is designed to fly in tandem with a Sentinel-3 satellite, combining its fluorescence data with Sentinel-3's optical and thermal measurements for a fuller picture of plant activity.

What is the Vega-C rocket?

Vega-C is an upgraded, more powerful version of Europe's Vega small-lift launcher. Standing around 35 metres tall, it uses a solid-propellant first stage (P120C), second and third solid stages, and a liquid-propellant upper stage (AVUM+) for precise orbital insertion. Vega-C is optimised for delivering Earth-observation and scientific payloads to polar and Sun-synchronous orbits, making it well suited to Copernicus and Earth Explorer missions like this one.

Where is the launch site?

The launch will take place at the Guiana Space Centre near Kourou, French Guiana, on the northeastern coast of South America. Its proximity to the equator makes it an ideal spaceport for reaching a wide range of orbits, and it serves as Europe's primary gateway to space for Ariane and Vega vehicles.

How to watch the launch live

ESA and Arianespace typically provide a live webcast beginning shortly before liftoff for major Copernicus and Earth Explorer missions. Because the launch is targeted for 00:00 UTC, viewers should convert this to their local time zone to catch the broadcast.

You can also follow the mission in real time on Cosmik. Watch the countdown on our latest launch news feed, and once the satellites reach orbit you can find them on our live 3D satellite map. Learn more about following spacecraft with our guide to tracking satellites.

Why does this mission matter?

Sentinel-3C and FLEX represent two complementary approaches to understanding our planet. Sentinel-3C continues an operational data record used daily by weather agencies, oceanographers and climate scientists, while FLEX opens a brand-new window on the global carbon cycle by measuring how efficiently plants are converting sunlight into energy. Together, launched on a single Vega-C, they strengthen Europe's leadership in Earth observation.

Follow the launch live on Cosmik

Don't miss liftoff. Track the Vega-C countdown on Cosmik, enable free launch alerts so you're notified before the window opens, and follow Sentinel-3C and FLEX on our live 3D map once they reach orbit.