Biomass is an European Space Agency mission designed to measure the density of carbon stored in the world’s forests. The spacecraft, built by Airbus Defence and Space, features the first civilian P-band synthetic aperture radar as well as a 12m-diameter deployable reflector from L3Harris made of over 900 km of gold-coated molybdenum 25µm wire. With a minimum operational lifetime of 5 years in its 666km 6am/6pm sun-synchronous orbit, the global coverage achieved every 9 months allows to precisely monitor the evolution of forests over time.