Japan to launch historic round-trip mission to Mars moon

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Japan is preparing to launch an uncrewed mission to retrieve material from Phobos, one of Mars’s two moons. According to an AFP report published by Citizen Digital on October 18, 2026, JAXA has scheduled the Martian Moons eXploration spacecraft, or MMX, to depart Tanegashima Space Center aboard an H3 rocket on Tuesday at 4:41 a.m. The project aims to complete the first return journey to the Martian system.

The spacecraft is expected to reach Mars’s vicinity a year after launch and spend up to three years orbiting Phobos before landing to gather at least 10 grams of surface material. A rover named IDEFIX will assess conditions ahead of the landing. MMX will also study Mars’s other moon, Deimos, without touching down there, before heading back to Earth.

Scientists hope the samples will help establish whether the moons formed from debris following an impact on Mars or were asteroids caught by its gravity. JAXA says resolving that question could improve understanding of how the Solar System developed. French astrophysicist Patrick Michel told AFP that the mission could also clarify how water and organic compounds reached rocky planets, helping create conditions suitable for life.

The mission brings together JAXA, US and European space agencies, and about 20 universities and technology companies. Japan has previously retrieved asteroid material: Hayabusa-2 delivered 5.4 grams to Earth in 2020. MMX faces different challenges, including landing in Phobos’s weak gravity and then escaping Mars’s gravitational pull. JAXA also hopes to assess whether Phobos could serve as a base for future exploration and help establish the requirements for crewed return trips to Mars.