Japan has fired the starting gun on one of the boldest sample-return missions ever attempted. On Monday, Oct. 19, the Japan Aerospace Exploration Agency (JAXA) launched its Martian Moons eXploration (MMX) spacecraft from the Tanegashima Space Center, beginning a five-year round trip to Phobos — the larger of Mars’ two moons — to scoop up surface material and bring it back to Earth.
The spacecraft lifted off at 3:41 p.m. U.S. Eastern time (4:41 a.m. Tuesday in Japan) aboard an H3 rocket, the tenth flight of Japan’s new flagship launcher. About 71 minutes later, JAXA confirmed the spacecraft had separated from the rocket’s upper stage and was on its planned trajectory toward Mars. “I believe we were able to place it into the planned orbit with exceptional precision,” said Makoto Arita, JAXA’s H3 project manager, at a post-launch press conference.
The stakes are historic. If the mission succeeds, MMX will be the first spacecraft to orbit Phobos, the first to land on and collect samples from the surface of a Martian moon, and the first to return material from the Mars system to Earth. The sample capsule is expected to land in Australia in July 2031 carrying at least 10 grams of Phobos rock and sand.
The journey is long: a roughly ten-month cruise, arrival at Mars in August 2027, then about three years of observation, a French-German rover called IDEFIX touching down on the surface, at least one landing and sample collection by the main spacecraft, and finally the long flight home.
Scientists are after a fundamental question: where did Mars’ moons come from? Phobos and Deimos may be captured asteroids — or debris blasted into orbit by a giant impact on Mars itself. The samples could settle the debate and rewrite our understanding of how the whole Martian system formed. NASA’s science chief Nicky Fox said the material could drive “fundamental discoveries about the Martian system for decades to come,” and the round-trip technology is a direct rehearsal for eventual crewed missions to Mars.
The mission is a genuinely international effort: NASA is contributing scientific instruments, sample-collection technology and navigation support, while the European Space Agency, France’s CNES and Germany’s DLR are partners. “The launch was spectacular,” said ESA’s MMX project scientist Elliot Sefton-Nash, congratulating JAXA.
The launch almost didn’t happen on this schedule. MMX was originally meant to fly in 2024, but trouble with the H3 rocket — whose maiden flight failed — pushed it back. Because Earth and Mars only line up for an efficient transfer about every 26 months, missing the window would have cost years. This time, the H3 flew cleanly: its third success in a row.