The Meteosat Third Generation Sounder (MTG-S1) satellite, carrying the Copernicus Sentinel-4 mission instrument, has been encapsulated in the Falcon 9 payload fairing and successfully launched at 23:03 CEST on 1 July. Last week, the final pre-launch activities and checks were completed smoothly, marking an important milestone for the teams involved, including the encapsulation of the satellite inside the fairing — the last time engineers could physically interact with it.

During preparations, MTG-S1 was first mated to the flight adapter — the structural interface that connects the satellite to the rocket and provides secure support during launch. The satellite's solar arrays remained folded, and its two scientific instruments — the infrared sounder and the Copernicus Sentinel-4 Ultraviolet-Visible-Near-Infrared (UVN) imaging spectrometer — were kept powered off during this phase. James Champion, ESA's MTG Project Manager, said: "Mating with the flight adapter involves both physical and electrical connections between the satellite and the adapter and requires extremely high precision and a high level of expertise."

After completing safety and functional checks, the satellite and its flight adapter were encapsulated inside the rocket's payload fairing, the conical structure that will protect it during the initial ascent phase. Propellant loading — a hazardous operation requiring the highest safety measures — was completed approximately two weeks before the scheduled launch date. With the final pre-launch activities concluded, MTG-S1 is now ready for flight and will operate in geostationary orbit to monitor severe storms and air pollution over Europe and North Africa. It will deliver temperature and humidity profiles at different altitudes across Europe every 30 minutes and aerosol, ozone, nitrogen dioxide, and sulphur dioxide data over Europe and Africa every 60 minutes. The Copernicus Sentinel-4 instrument will measure pollution every 60 minutes, transforming the way air quality is forecasted across Europe.