TOKYO, Japan / AsiaWire.IO / – A Japanese spacecraft has set off for Mars on a mission to explore the planet’s two small moons and bring back samples. The Japan Aerospace Exploration Agency launched the Martian Moons eXploration spacecraft, known as MMX, on an H3 rocket from the Tanegashima Space Center. Liftoff took place before dawn at 04:41 Japan time on Tuesday, October 20. The five-year mission aims to land a robotic spacecraft and a rover on Phobos.
Phobos is the larger and closer of Mars’ two moons. MMX is expected to become the first spacecraft to orbit Phobos and the first to collect samples from its surface. It also aims to be the first mission to return to Earth from the Mars system. JAXA leads the effort in collaboration with NASA, the French space agency CNES, the German Aerospace Center DLR and the European Space Agency. The rocket flew as planned, and spacecraft separation was later confirmed.
The mission seeks to answer a long-standing question about how the Martian moons formed. One theory, the giant impact hypothesis, holds that they formed after a massive body collided with Mars. Another, the capture hypothesis, suggests they are asteroids from the outer Solar System captured by Mars’ gravity. JAXA says remote-sensing observations and detailed analysis of the returned sample will help clarify their origin.
International partners supply rover and instruments
CNES and DLR provided a small rover called IDEFIX, which weighs less than 30 kg. The rover will land on Phobos before the main spacecraft and is designed to study how the surface responds to mechanical action while testing wheeled movement. NASA contributed a neutron and gamma-ray spectrometer called MEGANE. CNES also helped develop an infrared spectrometer and is contributing flight dynamics expertise. The spacecraft carries seven scientific instruments in total.
ESA provided deep space communication equipment, including a transponder and power amplifier. It will also support the mission through its Estrack network of ground stations. Elliot Sefton-Nash, ESA project scientist for MMX, said Japan’s H3 launcher performed fantastically to send the spacecraft on its way. ESA Director of Science Carole Mundell congratulated JAXA and the MMX team on the successful launch.
Sample set to return to Earth in 2031
MMX is expected to reach Mars about a year after launch, with ESA pointing to arrival next summer. The spacecraft will observe Phobos from a quasi-satellite orbit and survey candidate landing sites. It will then land and collect at least 10 grams of surface material. A coring sampler on a robotic arm can reach regolith deeper than 2 cm, while a pneumatic sampler uses pressurised gas to push soil into a container.
After its work at Phobos, MMX will observe Mars’ smaller moon, Deimos, during a flyby. It will then leave the Mars system for a journey of about one year back to Earth. The return capsule is scheduled to deliver its sample in 2031, with recovery planned in Australia. The mission was approved for development in 2020 and was originally targeted for a 2024 launch before the schedule moved to 2026.