Led by the Japan Aerospace Exploration Agency (JAXA), the Martian Moons eXploration (MMX) spacecraft is set to embark on a mission that aims to become the first in the world to bring back soil samples from Phobos, the larger of Mars’s two moons. The five-year expedition, carried out through international cooperation, could not only shed light on the mysterious origins of the Martian moons but also establish Phobos as a key staging point for future crewed missions to Mars.
Although the mission is spearheaded by the Japanese space agency, MMX is the result of a truly global collaboration, with NASA, the European Space Agency (ESA), and the French (CNES) and German (DLR) space agencies all playing key roles. The spacecraft will carry thirteen scientific instruments, including a gamma-ray and neutron spectrometer developed by NASA, a radiation monitor designed to assess the safety of future crewed expeditions, and European deep-space communications equipment.
The small robotic explorer is scheduled to make the first-ever landing on the moon around 2029. It will study the surface for approximately one hundred days and produce a detailed topographic map, enabling mission controllers on Earth to select a smooth, safe landing site for the mothership. The landing itself will pose an extraordinary technical challenge, as Phobos’s gravity is only about one two-thousandth of Earth’s. To prevent the MMX spacecraft from bouncing back into space upon touchdown, engineers have designed a specialized four-legged landing system with shock-absorbing capabilities. Meanwhile, the wheels of Idefix have been engineered to provide stable traction in microgravity and allow the rover to right itself if it tips over.












