Sentinel-1B lifted off on a Soyuz rocket from Europe’s Spaceport in Kourou, French Guiana, at 21:02 GMT, separating from the rocket’s Fregat upper stage 23 min 35 sec later.
Sentinel-1B joins its identical twin, Sentinel-1A, in orbit to deliver information for numerous services, from monitoring ice in polar seas to tracking land subsidence, and for responding to disasters such as floods.
“The launch of Sentinel-1B marks another important milestone as this is the first constellation we have realised for Copernicus,” said ESA’s Director General Jan Woerner.
“Orbiting 180 apart, the two satellites optimise coverage and data delivery for services that are making a step change in the way our environment is managed.”
Both satellites carry an advanced radar that images Earth’s surface through cloud and rain regardless of whether it is day or night.
During the launch, the satellite’s 12 m-long radar antenna and two 10 m-long solar wings were folded up to fit into the Soyuz rocket’s protective fairing. The solar wings and radar open together in a careful sequence that will take about 10 hours to complete.
Now that Sentinel-1B has been placed safely in orbit, the team of controllers at ESA’s operations centre in Germany will ensure that everything is working correctly and commission the satellite for operations.
Volker Liebig, ESA’s Director of Earth Observation Programmes, said, “We have seen some marvellous results from Sentinel-1A. Only two weeks ago, for example, it captured images of large icebergs breaking away from Antarctica’s Nansen ice shelf.
“Given that Antarctica is heading into winter now and daylight hours are getting shorter, radar images are vital to see what changes are taking place.
“With Sentinel-1B in orbit we will receive double the amount of data and achieve global coverage in six days.
“This is the fourth satellite that we’ve launched for Copernicus in just two years and this launch is certainly a special moment because it completes the Sentinel-1 constellation.”