








ABOUT
In FY 2026, the Martian Moons eXploration (MMX) mission will launch
towards Mars from the Tanegashima Space Center (TNSC)
in Kagoshima Prefecture.
This marks the first time
in approximately 28 years
that a spacecraft from Japan will head
to the Martian system.
MMX is humanity's first attempt to collect samples
from the Martian system,
aiming to gather material from the surface
of Mars's moon Phobos
and bring this back to Earth.
With departure in FY 2026,
we would like to request your messages
for the MMX team!
These messages will be carried
onboard the spacecraft
and returned to Earth six years later in 2031.
"Good luck, MMX!"
"To my future self in 2031...!"
We can't wait to read your messages!
MISSION
MISSION
The "Martian Moons eXploration (MMX)" is a mission to explore the moons of Mars that is scheduled for launch in FY2026 and return to Earth in 2031.
The spacecraft is approximately 5m tall and 9m long (including the solar panels) and will travel to Phobos, the innermost of Mars's two moons.The mission is to conduct scientific observations such as measurements of the moon's topography, internal structure, composition, and gravity, as well as collect and return a sample of the Phobos surface material to Earth.This data will help us investigate the origin of the Martian moons, and the evolution of our Solar System. MMX is an international collaboration led by JAXA, with collaborations with research institutes around the world, including NASA, CNES, DLR and ESA. Success will mark the world's first sample return from the Martian sphere.
STEP 01 [2026]
Launch onboard the H3 rocket
STEP 02 [2027]
After about 1 year, reach the Mars system. Aim for the moon, Phobos. This is the greatest challenge in the first half of the mission.
STEP 03 [2027-2030]
Observations of Phobos and the rover's advance landing will help the MMX spacecraft to land safely.
Sample collection on Phobos marks the peak of the mission.
Remain in the Mars system for three years, and observe the second Martian moon, Deimos.
STEP 04 [2030]
Departure from the Mars system.
STEP 05 [2031]
Return to Earth over the course of 1 year. The capsule will separate from the spacecraft and enter the atmosphere.
Capsule recovery is planned in Australia. This is the final critical stage of the mission.

























SEND MESSAGE
Messages of support have come to us from around the world,
and we'd love to collect yours too!
Contributors will receive an image of your onboard certificate!
-
STEP 01
Write your message!
Receive the boarding certificate -
-
STEP 02
After the submission period ends,
Your messages will be shared online
throughout the submission period. -
-
STEP 03
Departure from Earth
with your message in FY2026! -
-
STEP 04
Return to Earth
planned for 2031.
Your support will be with us
until the moment of return.