Sentinel-3B is a European Space Agency Earth observation satellite dedicated to oceanography which launched on 25 April 2018.

[1] It was built as a part of the Copernicus Programme, and is the second (after Sentinel-3A, launched 16 February 2016) of four planned Sentinel-3 satellites.

Sentinel-3B was successfully launched on 25 April 2018 at 17:57 UTC from the Plesetsk Cosmodrome aboard a Rokot launch vehicle.

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