On 15 September the European Space Agency (ESA) signed with the German company OHB the €129.4-million contract covering the detailed design, manufacturing and testing of the HERA mission. This mission, ESA’s first ever planetary defense mission, will be Europe’s contribution to an international asteroid deflection effort carried out jointly with NASA and due for lift-off in October 2024. The contract takes in the complete design of the interplanetary probe, integration and tests, including an advanced Guidance, Navigation and Control (GNC) system that has been awarded to GMV as subcontractor of OHB.

Asteroid approach and rendezvous operations are extremely demanding tasks. Their small size and mass, together with their irregular shapes and the unknown environment of deep space are all factors that make it very difficult to ensure safe control of spacecraft around asteroids. To cope with all these challenges GMV has developed an autonomous GNC system, providing this additional safety to guarantee mission success.

GMV is European GNC leader and ranks among the world’s pioneers in planetary and asteroid exploration missions. The company’s portfolio of European projects, featuring AIM, Marco POLO, Neoshield2, SYSNOVA-BEAST and Rosetta, has won GMV leadership in this field.

The GNC system developed by GMV for HERA autonomously runs the flight plan defined by human controllers on Earth, incrementally stepping up its autonomy level until it is calculating on board the maneuvers for flying at a certain altitude or executing an escape maneuver in case of potential collision risk. Both of these features are fundamental innovations of HERA’s GNC.

The tests to certify the technological readiness of GMV’s autonomous GNC system were carried out using a camera designed to work in space and a scale model of the Didymain-Dimorphos binary asteroid system. To ensure these tests were as realistic as possible, the deep space darkness conditions in which HERA will be working have been reproduced on ground. The April 2020 ground validation tests of the GNC system were first conducted in GMV’s optical laboratory and afterwards in GMV’s robotic laboratory called Platform-art^@ in Tres Cantos, Madrid, one of Europe’s most advanced robotic testbeds for validating GNC systems.