TOKYO, Japan / AsiaWire.IO / – Japan has launched a spacecraft bound for Mars on a quest to explore the planet’s mysterious moons and return samples to Earth. The Japan Aerospace Exploration Agency sent the Martian Moons eXploration (MMX) probe into space aboard an H3 rocket from the Tanegashima Space Center. The launch took place before dawn on Tuesday, October 20, at 04:41 local time. Five space agencies are working together on the five-year mission.
MMX will attempt to land a robotic prospector and a rover on Phobos, the larger and closer of Mars’ two small moons. If successful, it will be the first spacecraft to orbit Phobos, the first to collect samples from its surface and the first to return to Earth from the Mars system. JAXA leads the mission with NASA, France’s CNES, Germany’s DLR and the European Space Agency. Separation of the spacecraft from the rocket was confirmed after launch.
Scientists hope the mission will settle how Phobos and Deimos came to orbit Mars. The giant impact hypothesis proposes that the moons formed after a large body struck Mars. The capture hypothesis suggests they began as asteroids from the outer Solar System that were pulled in by Mars’ gravity. Observations from orbit and analysis of the returned material are expected to help determine which explanation is correct.
Rover and instruments come from global partners
The French and German space agencies built IDEFIX, a rover weighing less than 30 kg that will touch down on Phobos ahead of the main spacecraft. Its tasks include testing how the surface behaves under mechanical action and demonstrating wheeled travel. NASA supplied MEGANE, a neutron and gamma-ray spectrometer. The spacecraft carries seven science instruments, including an infrared spectrometer developed in partnership with CNES.
Europe is also providing key communications support. ESA delivered a transponder and power amplifier for deep space links and will use its Estrack ground station network to send commands and receive data. ESA Director of Science Carole Mundell congratulated JAXA and the MMX team on the launch. Elliot Sefton-Nash, the agency’s project scientist for MMX, praised the performance of the H3 launcher in sending the spacecraft on its way.
Sample return planned for 2031 in Australia
The spacecraft is expected to arrive near Mars roughly one year after launch. It will study Phobos from a quasi-satellite orbit and survey possible landing sites before touching down. MMX will collect at least 10 grams of material using two tools. A coring sampler on a robotic arm targets regolith deeper than 2 cm, while a pneumatic sampler fires pressurised gas to push soil into a container.
MMX will also attempt observations of Deimos, the smaller Martian moon, during a flyby. It will then depart the Mars system for a return trip of about one year. The sample capsule is due back on Earth in 2031, with recovery scheduled in Australia. JAXA first announced the mission in 2015, and development began in 2020 with a 2024 launch target before the schedule moved to 2026.