TOKYO, Japan / AsiaWire.IO / – On Tuesday, October 20, at 04:41 local time, Japan launched a spacecraft aimed at exploring Mars’ enigmatic moons and retrieving samples for Earth analysis. The Japan Aerospace Exploration Agency launched the Martian Moons eXploration (MMX) probe using an H3 rocket from the Tanegashima Space Center. The launch occurred just before dawn, marking the start of a five-year joint effort involving five space agencies.
The primary goal of MMX is to land a robotic prospector and rover on Phobos, the larger and nearer moon of Mars. If the mission succeeds, it will be the first to orbit Phobos, collect surface samples, and return material to Earth. The mission is led by JAXA, with participation from NASA, France’s CNES, Germany’s DLR, and the European Space Agency. Confirmation of spacecraft separation from the rocket was received after launch.
Scientists aim to clarify the origins of Phobos and Deimos, the two moons of Mars. The giant impact hypothesis suggests they formed after a large collision with Mars, whereas the capture hypothesis argues they are asteroids from the outer Solar System pulled in by Mars’ gravity. Data collected from orbit and returned samples are expected to shed light on which theory is correct.
Global partners contribute rover and scientific instruments
The French and German space agencies developed IDEFIX, a rover weighing less than 30 kg, which will land on Phobos ahead of the main spacecraft. Its functions include testing surface response to mechanical interaction and demonstrating wheeled mobility. NASA provided MEGANE, a neutron and gamma-ray spectrometer. The spacecraft carries seven scientific instruments, including an infrared spectrometer created in collaboration with CNES.
Europe provides essential communication support through ESA, which supplied a transponder and power amplifier for deep space links and will utilize its Estrack ground station network for command and data reception. ESA Director of Science Carole Mundell congratulated JAXA and the MMX team on the launch. Elliot Sefton-Nash, the project scientist for MMX at ESA, praised the performance of the H3 launcher in propelling the spacecraft on its journey.
Sample collection set for 2031 in Australia
Following a roughly one-year transit, the spacecraft is expected to reach Mars and will observe Phobos from a quasi-satellite orbit while surveying potential landing sites. During surface operations, MMX plans to gather at least 10 grams of material using two different tools. A coring sampler on a robotic arm will target regolith deeper than 2 cm, and a pneumatic sampler will use pressurized gas to propel soil into a container.
Additionally, MMX will perform flyby observations of Deimos, Mars’ smaller moon, before departing the system for a return journey of about one year. The sample capsule is scheduled to land back on Earth in 2031, with recovery efforts taking place in Australia. The mission was first announced by JAXA in 2015, with development starting in 2020, initially aiming for a 2024 launch before the schedule shifted to 2026.