English: The payload module of MetOp-C, Europe’s latest weather satellite, being lowered into Europe’s largest vacuum chamber, the 10 m-diameter Large Space Simulator.

The LSS is part of ESA’s Test Centre in the Netherlands, the largest facility of its kind in Europe, providing a complete suite of equipment for all aspects of satellite testing under a single roof.

MetOp-C’s MetOp-C’s instruments must be tested in space-like vacuum conditions. High-performance pumps will remove all air within the chamber to create an orbital-quality vacuum. Meanwhile, liquid nitrogen will circulate through the black walls to mimic the cold of sunless space.

MetOp is a set of three polar-orbiting satellites whose temperature and humidity observations from a relatively close 800 km-altitude orbit have sharpened the accuracy of weather forecasting.

Procured by ESA for Eumetsat, the European Organisation for the Exploitation of Meteorological Satellites, MetOp-A was launched in 2006 and MetOp-B in 2012, with MetOp-C due to follow next year.

The 2.1 tonne module carries a suite of meteorology and climatology instruments, variously procured by ESA or sourced from Eumetsat, France’s CNES space agency and the US National Oceanic and Atmospheric Administration.

Once testing is complete, MetOp-C’s payload module will travel to the Airbus Defence and Space facility in Toulouse, France, to be integrated with its service module – the segment of the satellite providing attitude and orbit control, electrical power and communications, and hosting the main computer.

The launch of MetOp-C by Soyuz from Europe’s Spaceport in French Guiana is scheduled for October 2018.