To monitor the entire planet’s surface, two types of satellite orbit are required.

Geostationary satellites provide a high altitude, fixed view of the portion of the planet’s surface below them, whilst low-earth orbiting satellites pass at low altitude over both poles, observing the section of ground directly below them in a series of more detailed ‘swathes’ which are knitted together to form a full picture.

EUMETSAT has been running a fleet of meteorological satellites, providing weather and climate data, for more than 25 years. The satellites are operated in these two orbits: Metop has a polar orbit 817km above the Earth, and Meteosat orbits in the geostationary ring around 36,000km away.