Copernicus Sentinel-4, which is set to play a key role in monitoring air quality over Europe, is ready to be fitted to its host, the first Meteosat Third Generation Sounder weather satellite.

Copernicus Sentinel-4 is a state-of-the-art ultraviolet, visible, near-infrared spectrometer instrument that has been developed to deliver hourly high-resolution measurements of trace gases such as nitrogen dioxide, ozone, sulphur dioxide and formaldehyde, as well as aerosols.