TOKYO, Japan / AsiaWire.IO / – A spacecraft headed for Mars has been launched by Japan to investigate its enigmatic moons and retrieve samples for analysis on Earth. The Japan Aerospace Exploration Agency launched the Martian Moons eXploration (MMX) probe using an H3 rocket from Tanegashima Space Center. The launch occurred early Tuesday morning, October 20, at 04:41 local time. The mission involves collaboration among five space agencies over a five-year period.
The primary goal of MMX is to land a robotic prospecting device and a rover on Phobos, which is the larger and nearer of Mars’ two small moons. If the operation succeeds, it will mark the first time a spacecraft orbits Phobos, collects surface samples, and returns them to Earth. JAXA is leading the effort, with partners including NASA, France’s CNES, Germany’s DLR, and the European Space Agency. The spacecraft was confirmed to have separated from the rocket after launch.
Researchers aim to resolve longstanding questions about the origins of Phobos and Deimos. The giant impact hypothesis suggests that the moons formed after a large object struck Mars. Conversely, the capture hypothesis proposes they originated as asteroids from the outer Solar System that were pulled into orbit by Mars’ gravity. Data from orbital observations and the analysis of returned material are expected to clarify which theory is correct.
International partners contribute rover and scientific instruments
The IDEFIX rover, developed by the French and German space agencies, weighs under 30 kg and will land on Phobos before the main spacecraft. Its functions include testing surface mechanical responses and demonstrating wheeled mobility. NASA contributed MEGANE, a neutron and gamma-ray spectrometer. The spacecraft also hosts seven scientific instruments, including an infrared spectrometer built in collaboration with CNES.
Europe is providing essential communication tools, including a transponder and power amplifier for deep space links. The ESA Estrack ground station network will facilitate command transmission and data reception. ESA’s 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’s performance in propelling the spacecraft into space.
Sample return mission scheduled for 2031 in Australia
Following a roughly one-year journey, the spacecraft will arrive near Mars and operate from a quasi-satellite orbit around Phobos, conducting site surveys before landing. It will collect a minimum of 10 grams of material using two devices: a coring sampler on a robotic arm targeting regolith over 2 cm deep, and a pneumatic sampler that uses pressurized gas to push soil into a container.
During its mission, MMX will also perform flybys of Deimos, the smaller Martian moon. After completing its surface sampling, the spacecraft will leave Mars’ vicinity for a return trip lasting about a year. The capsule containing the samples is scheduled to return to Earth in 2031, with recovery operations planned in Australia. The mission was first announced by JAXA in 2015, with development beginning in 2020. Originally slated for a 2024 launch, the schedule was later adjusted to 2026.