The European Space Agency and the Japan Aerospace Exploration Agency formalized a planetary defense partnership, locking in joint work on the Ramses spacecraft that will rendezvous with asteroid Apophis before its rare close pass by Earth in April 2029.
The Memorandum of Cooperation ends years of preliminary talks and gives Ramses — short for Rapid Apophis Mission for Space Safety — a confirmed second major partner. JAXA will contribute to the mission with technical components and will launch the probe on its H3 rocket. ESA retains responsibility for spacecraft design and mission operations.
A 375-meter rock on a path no one has seen before
Apophis, roughly 375 meters across, will pass approximately 32,000 kilometers above Earth’s surface on April 13, 2029 — a Friday the 13th coincidence that has not gone unnoticed. That distance places the asteroid below the orbit of geostationary communications satellites and at roughly one-tenth the distance to the Moon. According to Phys.org, an event of this scale and proximity occurs only once every 5,000 to 10,000 years for an object this large.
No impact risk exists. What does exist is a one-time scientific opportunity.
Earth’s gravity will physically reshape Apophis as it passes — tugging on its surface, possibly triggering landslides, altering its rotation, and stressing its interior structure. Ramses is designed to watch all of it happen in real time, before, during, and after the flyby.
Why the timing is brutal
The mission’s schedule is dictated by celestial mechanics, not budget cycles. To arrive at Apophis in February 2029 with weeks to spare before the flyby, Ramses must launch in a narrow window in 2028.
That leaves almost no margin for political delay. ESA’s ministerial conference was the gating event for full mission approval, with member states asked to commit funding for the next three years. Mission planners have indicated that the mission is hitting key milestones, with critical design review and spacecraft assembly underway.
Ramses borrows heavily from ESA’s Hera spacecraft, which launched in 2024 to study the Didymos binary asteroid system after NASA’s DART impact test. Hera was built in roughly four years from contract signature to launch — itself a record for an ESA deep-space mission. Ramses aims to beat that.
The diplomacy behind the hardware
Planetary defense has always been a strange domain politically. The threat is global, the response is national, and the timelines are geological. ESA and JAXA have framed their partnership as a deliberate institutional answer to that mismatch, with planetary defense characterized as a global responsibility requiring concrete implementation beyond shared intention.
The agencies have signed both the Memorandum of Cooperation and a separate agreement to advance work on planetary defense.
The Japanese contribution matters for reasons beyond cost-sharing. JAXA brings hard-won small-body expertise from the Hayabusa and Hayabusa2 sample-return missions, which successfully visited and returned material from asteroids Itokawa and Ryugu. That operational heritage at near-zero-gravity bodies is rare. Few agencies have it.
The cooperation builds on the existing Hera partnership and is meant to strengthen ties between the two scientific communities, not just the agencies.
What scientists actually want to learn
Apophis matters for planetary defense not because it threatens Earth but because it offers a free experiment. Researchers have models of how tidal forces from a planetary close approach should deform a small asteroid. None of those models has been tested against a real event at this scale.
The flyby will probe Apophis’s internal structure — whether it is a solid monolith, a rubble pile held together by gravity and friction, or something in between. That distinction matters enormously for any future deflection attempt. A kinetic impactor like DART transfers momentum very differently to a coherent body than to a loose aggregate of rocks. Get the assumption wrong, and a deflection mission could fragment an asteroid rather than nudge it.
Ramses will also map surface features in detail before the flyby, then again afterward, to catalogue any changes — fresh boulder movements, new slumps, altered rotation rates. ESA selected OHB Italia as prime contractor for the spacecraft, and a second CubeSat has been added to the mission to enable close approaches the main spacecraft cannot safely perform.
An audience of two billion
Apophis will be visible to the naked eye for an estimated two billion people, primarily across Europe, Africa, and western Asia. That is a planetary defense communications event without precedent. Most asteroid flybys are detected only by professional observers using telescopes; this one will track across the night sky as a moving point of light brighter than many stars.
The public dimension has not escaped commercial actors. James Orsulak, co-founder of ExLabs and chairman of the Planetary Defense Trust, told Space.com that the company is pursuing partnerships with IMAX and others to broadcast the flyby as a live event, suggesting it could draw higher viewership than the Super Bowl. The disparity in planetary defense funding compared to overall space budgets remains a point of concern among advocates.
The challenge for planetary defense is not just detection or deflection technology, but building the industrial capacity to respond quickly — the ability to build and launch a response spacecraft within months rather than decades.
The bigger pattern
Ramses is one piece of a slowly assembling planetary defense architecture. NASA’s DART proved kinetic deflection works against a small asteroid moonlet. Hera is now characterizing the aftermath at Didymos. OSIRIS-APEX, the renamed and redirected OSIRIS-REx spacecraft, will reach Apophis after the 2029 flyby and stay for an extended study. Ramses fills the gap none of the others can: presence at Apophis during the flyby itself.
Space Daily has previously covered the Ramses spacecraft and cubesat contracts, the addition of the second CubeSat, and the OSIRIS-APEX trajectory toward Apophis.
The project operates under a hard constraint: nature picks the schedule, Apophis will not wait, and political processes have to align with that fact.
The next test is execution. Spacecraft assembly is the easy part compared to coordinating two agencies, one prime contractor, multiple member states, and a launch vehicle on a fixed celestial deadline. If Ramses arrives on time in February 2029, it will mark the first time a spacecraft has watched a planetary-scale gravitational experiment unfold on an asteroid in real time.
If it does not, the next opportunity to study an Apophis-class object at this proximity is several thousand years away.
Photo by SpaceX on Pexels
