The European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA) have signed a Memorandum of Cooperation to expand collaboration on planetary defence, alongside a separate agreement covering the Ramses (Rapid Apophis Mission for Space Safety) mission to the near-Earth asteroid Apophis.
The agreements were signed on 7 May by ESA Director General Josef Aschbacher and JAXA President Hiroshi Yamakawa at the Embassy of Italy in Berlin, Germany, with European and Japanese institutional and industrial representatives present. The event was hosted in collaboration with the Italian Space Agency (ASI), following ESA’s selection of OHB Italia as prime contractor for the Ramses mission.
The move builds on a joint statement from November 2024 in which ESA and JAXA said they would expand large-scale cooperation, including in planetary defence.
“Planetary defence is, by definition, a global responsibility,” Aschbacher said. “With today’s signatures, ESA and JAXA are moving decisively from shared intention to concrete implementation, translating commitment into mission‑level cooperation. This partnership builds on trust, technical excellence and a shared determination to protect our planet.
“In an increasingly complex environment, international cooperation remains a cornerstone of Europe’s approach to space. Together, ESA and JAXA are showing how reliable partners turn ambition into action for the benefit of all.”
Yamakawa added: “We are pleased to have signed today the Memorandum of Cooperation and the agreement to advance cooperation on planetary defence. We sincerely appreciate ESA and its Member States, including Italy, and expect this cooperation to further advance international efforts in this field.”
A global effort
Planetary defence focuses on detecting and characterising near-Earth objects, tracking their trajectories, assessing impact risks, and developing mitigation strategies. ESA said closer ESA–JAXA cooperation is intended to support those activities.
ESA’s role includes its Space Safety programme and the Near-Earth Object Coordination Centre (NEOCC), which monitors asteroid threats and refines orbit predictions. ESA cited its Hera planetary defence mission—on which JAXA is a partner—as an example of ongoing work, with Hera due to arrive later this year at the Didymos binary asteroid system to study the outcome of a kinetic-impact deflection test.
The Ramses mission to Apophis
ESA said the first major outcome of the new cooperation is collaboration on Ramses, which is planned to launch in 2028 and rendezvous with asteroid (99942) Apophis ahead of its close Earth flyby in April 2029.
Apophis is around 375 metres across and is expected to pass about 32,000 km above Earth’s surface on Friday 13 April 2029, which ESA said is closer than satellites in geosynchronous orbit and about one tenth of the distance to the Moon.
ESA said there is no risk of impact, but described the flyby as rare on timescales of 5,000 to 10,000 years for an object of this size. The agencies said the event will provide an opportunity to study how Earth’s gravity affects an asteroid’s shape, surface and motion.
Under the current division of responsibilities, ESA is to oversee Ramses spacecraft design, integration and operations. JAXA is to provide lightweight solar arrays, an infrared imager, and the launch on its H3 rocket. ESA said the partnership builds on JAXA’s contribution to Hera and existing ESA–JAXA collaborations including EarthCARE and BepiColombo.
ESA said observations before and after the flyby are expected to improve understanding of asteroid structure and behaviour relevant to future deflection planning.
