It is a revolutionary eye in the sky in what has been dubbed the most ambitious Earth observation venture ever.
European radar satellite Sentinel-1a is being launched on Thursday.
A fleet of other Sentinels will follow in coming years as part of Copernicus, a monitoring initiative led by the European Commission and European Space Agency (ESA).
Each satellite will be able to provide imagery in near real time, the rapid data a major boost in dealing with emergencies.
“It will be able to monitor basically all surfaces of the earth, the ocean, the ice surfaces, land surfaces and it will react very quickly in case of natural disasters to support imagery to the support teams on the ground,” said ESA Spacecraft Operations Manager, Frank Juergen Diekmann.
Sentinel 1-a will begin its all-important mission later on Thursday, launched into space from French Guiana on a Soyuz rocket.
