Beyond Gravity composites, space instruments power European MetOp weather satellites

Radio occultation (RO) instrument from Beyond Gravity. GRAS’ zenith-pointing antenna tracks a number of GPS satellites in range. This is indicated by the blue lines. The track-line changes to yellow once the signal goes into occultation as it is in range of the GAVA antenna. From these signals, profiles can be derived for the lowermost 80 kilometers of the Earth's atmosphere. The red line indicates where a rise event begins and the signal is received by the GVA antenna. Source | ESA – AOES Medialab

MetOp-Second Generation (MetOp-SG), a new generation of polar-orbiting European weather satellites manufactured by Beyond Gravity (Zurich, Switzerland), will be launched into space aboard the Ariane 6 launch vehicle Aug. 13, 2025. The 6-meter, 1-ton structures, made of carbon fiber, aluminum and titanium for critical connections, will measure humidity and temperature as well as aerosols.

“This weather satellite, together with its five counterparts, will significantly enhance weather forecasting accuracy and climate change monitoring,” says Oliver Grassmann, executive VP satellites at Beyond Gravity. “A key element of this mission is our radio occultation [RO] instrument, which provides important weather data.” RO in space measures how radio signals from satellites bend as they pass through Earth’s atmosphere, helping understand weather, climate and atmospheric conditions. “The instrument will more than double the number of occultations to 2,100 per day per instrument … and will provide RO data until 2050.”

In addition to this instrument, Beyond Gravity provided the satellite’s primary structure, thermal insulation and multiple products for the Ariane 6 launcher. The prime contractor for the satellite is Airbus Defence and Space (Toulouse, France).

European MetOp weather satellites have been orbiting the Earth from the North Pole to the South Pole since 2006. With this satellite, the first of six weather satellites of the latest generation, MetOp-SG, will be launched into space and will join the existing two MetOp weather satellites of the first generation already in orbit. These satellites will ensure the continued global observations from polar orbit. In the coming years, the other MetOp-SG satellites will be launched. With climate change driving more frequent and severe extreme weather events, precise and timely weather forecasting has never been more critical.

In total, MetOp-SG consists of six satellites: three successive pairs made up of an A-type and a B-type satellite, which carry a host of different but complementary instruments. The current satellite is an A-type (MetOp-SG-A). The A-type satellites also carry Copernicus Sentinel-5 ultraviolet, visible, near-infrared and shortwave infrared to measure key air pollutants and climate-related gases. The MetOp-SG mission has been developed in a long-standing cooperation between the ESA and Eumetsat.

Sealing the MetOp-SG-A1 satellite within the Ariane 6 fairing before its launch. Source | ESA-CNES-ARIANESPACE/Optique vidéo du CSG–T. Leduc

The first MetOp-SG satellite was constructed at Beyond Gravity’s site in Zurich. The metal-composite structure is wrapped in thermal insulation to protect it from high-temperature fluctuations of ±200°C in space, keeping the interior of the satellite at a constant room temperature to ensure the smooth functioning of the instruments on board. The insulation consists of several layers of very thin metal-coated plastic and was produced in Berndorf, Austria.

The top of the Ariane 6 rocket, on which MetOp-SG will be launched, consists of the payload fairing from Beyond Gravity made of carbon fiber composite. The fairing has a diameter of 5.4 meters. Produced at the Beyond Gravity site in Emmen, Switzerland, the two halves of the payload fairing protect the satellite from the harsh forces experienced during launch and the early flight stages.

Beyond Gravity’s site in linköping, Sweden, provided the payload adapter system for Ariane 6 as well. The payload adapter system connects satellite and launcher during liftoff, then precisely releases the satellite into orbit once the proper altitude is reached.

In Austria, Beyond Gravity also produced the high-temperature insulation for the rocket engines of the launcher’s lower and upper stage as well as the engine gimbal for alignment of the rocket’s upper stage. This rocket engine insulation consists of glass fabric and polymer films.