TOKYO, Japan / AsiaWire.IO / – The Japan Aerospace Exploration Agency has initiated a spacecraft journey aimed at investigating Mars’s enigmatic moons and retrieving samples to bring back to Earth. The Martian Moons eXploration (MMX) probe was launched into space aboard an H3 rocket from the Tanegashima Space Center. The launch occurred before dawn on Tuesday, October 20, at 04:41 local time. The mission involves collaboration among five space agencies over its five-year duration.
MMX’s objectives include landing a robotic prospector and a rover on Phobos, which is the larger and closer of Mars’ two small moons. If the mission succeeds, it will be the first spacecraft to orbit Phobos, to collect surface samples, and to return to Earth from the Mars system. JAXA is leading this effort, with partners including NASA, France’s CNES, Germany’s DLR, and the European Space Agency. Confirmation of spacecraft separation from the rocket was received following launch.
Researchers aim to clarify how Phobos and Deimos came to orbit Mars. The giant impact hypothesis suggests that the moons formed after a large body collided with Mars, whereas the capture hypothesis proposes they originated as asteroids from the outer Solar System pulled in by Mars’ gravity. Data from orbiting observations and the analysis of the returned materials are expected to shed light on which theory holds true.
Global partners supply rover and scientific instruments
The French and German space agencies developed IDEFIX, a rover weighing under 30 kg, which will land on Phobos prior to the main spacecraft. Its roles include testing surface interactions under mechanical stress and demonstrating wheeled mobility. NASA contributed MEGANE, a neutron and gamma-ray spectrometer. The spacecraft carries seven scientific instruments, including an infrared spectrometer created in collaboration with CNES.
Europe plays a vital role in communication support, providing a transponder and power amplifier for deep space links. The ESA will utilize its Estrack ground station network to send commands and gather data. ESA Director of Science Carole Mundell congratulated JAXA and the MMX team on the launch, while Elliot Sefton-Nash, the project scientist for MMX, praised the H3 launcher for its performance in sending the spacecraft on its mission.
Sample collection scheduled for 2031 in Australia
The spacecraft is projected to reach Mars vicinity approximately one year after launch, where it will observe Phobos from a quasi-satellite orbit and evaluate potential landing sites before touchdown. It will gather a minimum of 10 grams of material via two different tools: a coring sampler on a robotic arm designed to target regolith deeper than 2 cm, and a pneumatic sampler that uses pressurized gas to push soil into a container.
During a flyby, MMX will also perform observations of Deimos, Mars’ smaller moon, before departing the planet’s vicinity for a return journey of about one year. The sample capsule is scheduled to arrive back on Earth in 2031, with recovery efforts planned in Australia. JAXA initially announced the mission in 2015, with development starting in 2020. The launch was originally targeted for 2024 but was later rescheduled to 2026.