European Space Agency

ESA built the European Service Module 2 that powered Orion on the Artemis II lunar flyby, completed 10 April 2026. The module's main engine delivered translunar injection so precisely that two planned correction burns were unnecessary. However, the O2 manifold pressurisation valve leaked at 10 times the ground-test prediction throughout the mission, and ESM-2 burned up on re-entry before any post-mission data could be extracted. ESA issued a press statement on 11 April praising TLI precision but omitting the valve anomaly. A further communication on 16 April also omitted the anomaly, deferring technical review to the June 2026 ministerial council.

Founded in 1975, ESA coordinates the space activities of 22 member states. The ESM programme grew from heritage Automated Transfer Vehicle technology. ESM-3, built for Artemis III, arrived at KSC from Bremen in August 2024 and has completed initial power-up in the Armstrong Operations and Checkout Building. Whether ESM-3 incorporates a corrected valve design is publicly unanswered.

ESA's REMIT extends well beyond crewed exploration. Its Copernicus Earth-observation programme, including the freely available Sentinel-2 imagery satellites, has become a default open-source intelligence tool for conflict monitoring: Sentinel-2 passes were used in July 2026 to confirm impact scars inside the Bushehr nuclear plant's boundary during the Iran conflict, and separately to document Cuba's collapse in nighttime lighting. That civilian data mission sits alongside ESA's structural stake in Artemis: without the ESM, Orion cannot reach the Moon, but that leverage is now complicated by the ESM-2 valve disclosure gap, which member states will need to assess at the June Council before authorising continued investment in ESM-4 and beyond.