Following on from the launch of the first Meteosat Third Generation weather satellite, MTG-I1, last December, the focus is now on getting its partner satellite, MTG-S1, ready for liftoff next year – and a significant milestone has been reached. The satellite has been equipped with its main instrument, the Infrared Sounder, hence the satellite’s name, and also the Copernicus Sentinel-4 instrument, an ultraviolet, visible, near-infrared light spectrometer, or UVN for short.