Japan Launches MMX, a Mission to Bring Home the First Samples From a Martian Moon
JAXA's spacecraft is on its way to Phobos, with NASA, ESA, France and Germany contributing and samples due back on Earth by 2031.
Japan's space agency JAXA launched its Martian Moons eXploration (MMX) spacecraft on October 19 (EDT) aboard an H3 rocket from the Tanegashima Space Center. It is bound for Mars and its two small moons, Phobos and Deimos, and is designed to return a sample from Phobos by 2031.
The plan
MMX will travel to the Mars system, study both moons, and land on Phobos to collect at least 10 grams of material, according to reporting from Space.com. A small French-German rover named Idefix is meant to scout the surface. JAXA leads the mission, with partners including NASA, France's CNES, Germany's DLR and the European Space Agency.
- Launch: October 19, 2026 (EDT), October 20 in Japan, on an H3 rocket
- Arrival at Mars: expected in 2027
- Sample return: targeted for 2031, with the capsule due to land in Australia
Why scientists care
Nobody has yet brought back material from a moon other than Earth's. Phobos, a lumpy body roughly 22 kilometres across, may have formed from debris thrown up by a giant impact on Mars, or may be a captured asteroid. Pieces of it could help settle that question and reveal more about Mars' early history.
A long road ahead
This is a launch, not a result: the spacecraft still has years of travel, a delicate landing and a return trip ahead. The mission was originally aimed at 2024 and was delayed, and launch windows to Mars open only about every 26 months, so hitting this one matters.
JAXA has previously returned samples from two asteroids, Ryugu and Itokawa, which is part of why many researchers are optimistic about this next step.
