MetOp-SG-B1 enters cleanroom preparations for a late-year launch

The European weather satellite has left storage in French Guiana. Reactivation, testing and fuelling still lie ahead before an Ariane 6 launch targeted for late 2026.

Europe's MetOp Second Generation-B1 weather satellite has been moved into a cleanroom and unpacked in French Guiana, ESA reported on November 4. Engineers are preparing to switch it on and begin the final campaign for an Ariane 6 launch planned towards the end of 2026.

Out of storage, with checks still ahead

The spacecraft reached Kourou on October 16 after a sea journey from Bordeaux aboard Canopée. It initially remained inside its transport container, in a dry nitrogen environment maintained at 22°C. That protected the hardware while the team waited to start launch preparations.

The next steps include reactivation, final checks and fuelling. The satellite must then be enclosed inside the rocket's protective fairing and taken to the launch pad. ESA's update confirms that unpacking has happened; it does not announce a completed test campaign or a precise launch date.

Measuring more than the appearance of clouds

B1 is intended to work alongside MetOp-SG-A1, launched on August 13, 2025. The two types carry different instruments, allowing the programme to combine several kinds of atmospheric and surface measurements rather than rely on one view.

On B1, the Scatterometer, or SCA, is a radar instrument designed to retrieve ocean-surface wind speed and direction, as well as land-surface soil moisture. Its measurements describe physical conditions, rather than the colours of a visible-light photograph.

The Microwave Imager is designed to measure precipitation and sea-ice extent. The Ice Cloud Imager adds measurements of ice within clouds, including its amount, properties and altitude. EUMETSAT's instrument overview shows how these observations complement the A-type satellite's temperature, humidity and other measurements.

These are different pieces of the weather picture. A photograph can reveal a storm's cloud pattern; the B-type instruments are built to supply additional quantities relevant to forecasting and climate research. Their intended capabilities are not yet measurements from B1.

Getting observations into forecasts

The satellites are designed for near-polar orbits about 832 kilometres above Earth, circling the planet roughly 14 times a day. The wider programme uses three successive pairs to sustain observations for more than 20 years; that is a programme duration, not the lifetime promised for this single spacecraft.

Launch will be followed by deployment, early systems checks and in-orbit commissioning. Under the planned operations and data-processing chain, EUMETSAT manages routine satellite operations and turns instrument readings into calibrated, geographically located observations and derived weather products.

For now, the confirmed progress is on the ground. B1 has left its protective container, while the work needed to launch it and validate its observations remains ahead.