ESA’s new Earth observation satellite Sentinal-3A will soon be launched into orbit. Once more the European Space Agency proves it is on the forefront of monitoring our environment and the climate. Using state of the art and proven technology the Sentinel-3 satellite is a fabulous piece of engineering set to play a key role in the European Commission’s Copernicus programme. However this technological piece of craftsmanship is only possible as the result of earlier scientific missions such as ERS, Envisat and Cryosat, with Sentinel-3 building on their heritage.