Japan's MMX launches to bring back a sample from Mars' moon Phobos

Japan's space agency JAXA launched its Martian Moons eXploration (MMX) spacecraft on October 20, 2026, at 4:41 a.m. Japan time (October 19 in the Americas). An H3 rocket carried it from the Tanegashima Space Center, and the spacecraft separated about 71 minutes after liftoff into its planned path.

MMX is a sample-return mission to Phobos, the larger of Mars' two small moons. If all goes to plan, it will be the first spacecraft to orbit Phobos, the first to collect material from its surface, and the first to make a round trip from the Mars system back to Earth.

The plan

The cruise to Mars takes about a year, so MMX should arrive in 2027. It will then spend about three years near Phobos in a special "quasi-satellite" orbit that keeps it close to the little moon. The plan calls for two soft landings on Phobos to collect at least 10 grams of surface material, plus observations of the outer moon, Deimos, late in the mission. MMX leaves Mars in 2030, and a capsule carrying the sample is due to land in Australia in 2031.

Where did Mars' moons come from?

Phobos and Deimos are tiny, dark and lumpy, and scientists still debate their origin. One idea is that they are captured asteroids. Another is that they formed from debris thrown up when a large body slammed into Mars. A sample from Phobos, studied in labs on Earth, could settle the question and tell us more about early Mars.

The mission is an international effort. NASA supplied MEGANE, a gamma-ray and neutron spectrometer built by the Johns Hopkins Applied Physics Laboratory with Lawrence Livermore National Laboratory, which will map the chemical elements on Phobos' surface. ESA provided deep-space communications equipment and ground station support, and the French and German space agencies CNES and DLR are also partners.

Phobos and Deimos are hard targets for backyard telescopes because they sit so close to bright Mars, but Mars itself is easy to spot before dawn this month in the eastern sky near Jupiter. Read more on our Mars page.

What comes next: MMX now begins its cruise to Mars, with arrival expected in 2027 and science operations at Phobos through 2030.