Japan launched an uncrewed spacecraft toward the Martian moon Phobos on October 20, 2026, aiming to become the first nation to collect surface samples from the rocky body and return them to Earth for analysis in a multi-agency mission lasting five years.
The Martian Moons Exploration (MMX) mission lifted off from the Tanegashima Space Center in southern Japan using an H3 rocket. The 5-ton spacecraft departed on an ambitious five-year journey developed by the Japan Aerospace Exploration Agency to study Mars and its two natural satellites.
Japan Launches Spacecraft From Tanegashima
Thousands of spectators gathered early in the morning to watch the liftoff at 4:41 a.m. local time. Flight controllers confirmed the spacecraft successfully separated from the rocket’s upper stage. The mission involves contributions from multiple international space agencies.
Japan is investing 350 million dollars into the project. Additional financial and technical backing comes from NASA at about 6 million dollars. The French space agency contributes roughly 68 million dollars.
The German space agency provides approximately 56 million dollars. The European Space Agency contributes 17 million dollars.
Martian Moons eXploration (MMX) aboard the H3 Launch Vehicle No. 10 is set to launch on October 20!Watch the launch live via the link below 🔽https://t.co/UErHam1XcI🎥 Activity Report Mini#MMX #H3F10 #JAXA pic.twitter.com/tSTDIxyYAA
Rover Operates On Phobos Surface
The spacecraft is scheduled to reach the vicinity of Mars in late summer, where it will enter orbit around Phobos. Before the main lander touches down, the mothership will deploy a small Franco-German rover named Idefix.
Idefix is designed to operate in the extremely low gravitational pull of the 22-kilometer-wide potato-shaped moon. Weighing about 25 kilograms and built no larger than a microwave oven, Idefix will spend roughly 100 days scouting the rugged terrain. Because gravity on Phobos is roughly 2,000 times lower than on Earth, the surface features exceptionally weak pull. To prevent the lander from becoming unstable during touchdown, the MMX landing module is equipped with a four-legged shock-absorbing system. The rover is designed to operate in low gravity and right itself if it flips over.
This is a once-in-a-lifetime opportunity. We are part of the first mission to bring samples back from the Martian system. Markus
German Space Agency rover lead Markus Grebenstein emphasized the unique nature of the endeavor, which scientists involved have called a once-in-a-lifetime opportunity. Following the rover’s scouting phase, the four-legged main lander will touch down on the surface in late 2028 or 2029.
Spacecraft Collects Samples For Return
The main spacecraft will spend only about two hours on the surface of Phobos to gather at least 10 grams of material using dual extraction methods. An American tool will utilize pressurized gas to blow surface dust into a container.
A Japanese coring device will drill about two centimeters into the regolith. The collected samples will be secured inside a specialized return capsule designed to withstand the intense heat of reentry into Earth’s atmosphere.
The mission plan dictates that the spacecraft will leave Martian orbit in November 2030, swing past the second moon Deimos for further study, and deliver the sample capsule to the Australian desert in 2031.
Samples Target Martian Origins Debate
Scientists hope the returned samples will resolve a long-standing debate. Previous international attempts to explore Phobos—including multiple Soviet missions and Russia’s 2011 Phobos-Grunt effort—encountered severe failures.
By historical comparison, NASA astronauts brought about 382 kilograms of rocks and dust back to Earth during the Apollo 11 through Apollo 17 missions between 1969 and 1972. Later, the Soviet Union’s uncrewed Luna-24 mission safely delivered approximately 170 grams of lunar soil to Earth in 1976. China more recently collected nearly 2 kilograms of new material through its Chang’e-5 and Chang’e-6 campaigns.
While NASA has successfully landed nine spacecraft on the Martian surface and China landed a rover in 2021, no mission has yet reached or returned material from either Martian moon. China is currently targeting its own sample-return mission for 2028 with a similar 2031 return goal, setting up a potential race to analyze the first pristine material from the Martian system.
