While the Copernicus Sentinel-3A satellite is in orbit delivering a wealth of information about our home planet, engineers are putting its twin, Sentinel-3B, through a series of vigorous tests before it is shipped to the launch site next year.

The Sentinel-3 mission is designed as a two-satellite constellation to give optimum global coverage and data delivery for Europe's environmental monitoring Copernicus programme.

Sentinel-3A has been in orbit since February 2016 and will be joined by Sentinel-3B next year.