ESA’s Hera spacecraft launched on 7 October 2024 and is travelling to the Didymos binary asteroid system, where it will rendezvous in late 2026. Its destination is the approximately 780-metre-wide Didymos and its 151-metre moonlet Dimorphos, whose orbit NASA’s DART spacecraft altered by kinetic impact in 2022. Hera will conduct the first detailed post-impact survey of a human-modified asteroid system, including high-resolution imaging, laser and radio mapping, and measurements of Dimorphos’s mass, orbit, crater and internal structure.[1][3][5]
The mission will quantify how asteroid composition, structure and ejecta determine deflection outcomes. Hera may operate as close as 200 metres from Dimorphos with approximately 2-centimetre imaging resolution, while its Juventas CubeSat will perform the first radar sounding of an asteroid interior.[5][6] These capabilities address a direct existential risk: a lunar settlement cannot survive an unmitigated impact unless civilisation maintains reliable detection, trajectory prediction and deflection systems. Hera also advances autonomous navigation, ultra-low-gravity operations and inter-satellite communications relevant to distributed lunar and deep-space infrastructure.[5][6]
The Ark team should integrate Hera and the NASA DART results into its planetary-threat doctrine and preserve the mission’s engineering and scientific data in redundant lunar archives. Track the 2026 rendezvous, Hera’s measured Dimorphos mass and orbital change, its impact-crater and interior findings, and the performance of autonomous proximity operations. Use the resulting evidence to define asteroid-warning timelines, deflection mission architectures, spacecraft autonomy requirements and lunar shelter standards for impact scenarios.[1][5][6]