Sylvain Lodiot, heading ESA’s Outer Solar System and Planetary Defence Operations, explains: “The testing involved running the software on a functional replica of Hera located at the mission’s prime contractor OHB in Bremen, called the ‘Bench’, flying around simulated models of the asteroids and communicating with actual CubeSat replicas though the inter-satellite links.”

Caglayan Guerbuez, Hera Spacecraft Operations Manager.: “It’s not so unusual that a deep space mission is launched without its final software aboard, but Hera was really a mission in a hurry: it had to launch when it did in October 2024 in order to benefit from a flyby past Mars the following spring, otherwise the mission would have taken years longer to reach Dimorphos.