Japan Aerospace Exploration Agency (JAXA) will launch its Martian Moons eXploration (MMX) mission on October 20, 2026, from the Tanegashima Space Center, according to agency announcements. The $345 million mission aims to collect rock samples from Mars’s moons, Phobos and Deimos, and return them to Earth by 2031. It marks Japan’s first Mars probe launch in 28 years.
MMX Mission Timeline and Flight Architecture
The MMX spacecraft will take approximately one year to reach Mars after its 2026 liftoff. According to mission specifications, the probe will spend three years operating in orbit around the red planet to collect samples before embarking on a one-year return trip to Earth. Mitsubishi Electric designed the spacecraft, which carries fuel split into three distinct reserves for the outward journey, exploration phase, and return flight.
Autonomous Navigation and Phobos Landing Challenges
Landing on Phobos presents severe engineering hurdles due to the moon’s tiny radius of roughly 11 kilometers. According to JAXA technical briefings, Phobos has a gravitational pull about 300 times weaker than Earth’s Moon, yet roughly 50 times stronger than asteroid Ryugu, where JAXA previously landed a probe. Because hovering—the standard landing method for smaller bodies—would consume too much fuel under Phobos’s gravity, MMX relies on high-precision autonomous navigation to manage a 20-minute radio signal delay with Earth.
Did you know? The MMX rover, named IDEFIX, was developed jointly by the French and German space agencies. It will spend 100 days surveying the surface of Phobos ahead of the main spacecraft’s arrival.
Sampling Phobos and the Search for Martian Debris
Scientists estimate that roughly 0.1 percent of the collected material will consist of debris blasted off Mars by past meteorite impacts. This dual-source material will help researchers determine whether Phobos and Deimos formed from a giant impact ring or originated as captured asteroids from the outer solar system.
Frequently Asked Questions
When is the MMX spacecraft launching?
According to JAXA, the MMX mission is scheduled to launch on October 20, 2026.
When will the samples return to Earth?
Mission planners expect the Martian moon samples to arrive on Earth in 2031.
How much will the JAXA Mars mission cost?
The MMX mission carries an estimated price tag of $345 million.
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