The short version
- Japan successfully launched the MMX spacecraft aboard an H3 rocket, marking the first attempt to land on and retrieve samples from Mars’s moon Phobos.
- The mission involves a collaborative effort among five space agencies, utilizing a French-German rover to scout landing sites before a Japanese lander collects soil and rock.
- Scientists aim to determine whether Phobos formed from a giant impact or was captured as an asteroid, insights that could clarify the origins of life on Earth.
Japan has initiated a groundbreaking space mission designed to retrieve physical samples from Phobos, one of the two moons orbiting Mars. The Martian Moons Exploration spacecraft departed from the Tanegashima Space Centre in the country’s southwestern region early Monday morning. Powered by the nation’s flagship H3 rocket, the unmanned probe separated successfully from its upper stage approximately one hour after liftoff, prompting celebrations within the flight control center. This launch represents a significant milestone in planetary science, as it marks the first time any space agency has attempted to land on either of Mars’s small, irregularly shaped satellites.
The mission is structured as a multi-year endeavor with a planned arrival at Mars orbit in August of next year. Upon reaching the Red Planet, the five-tonne spacecraft will synchronize with Phobos’s rapid orbital path. The moon, which measures roughly 14 miles in diameter and circles Mars three times daily at an altitude of about 6,000 kilometers, presents unique challenges due to its low gravity and pock-marked surface. The primary objective is to collect at least 10 grams of soil and rock from the lunar surface before returning to Earth in 2031.
International cooperation plays a central role in this ambitious project. Five space agencies are collaborating on the five-year initiative, which carries a price tag of approximately $578 million. A key component of the early phase involves the deployment of Idefix, a small rover developed by France and Germany. Named after the comic book character’s dog, this four-wheeled vehicle is designed to bounce across Phobos’s surface due to the moon’s extremely weak gravitational pull, which is roughly one-thousandth that of Earth. The rover will spend about 100 days surveying the terrain to identify safe zones for the main lander.
Following the scouting phase, a stationary, four-legged Japanese lander will descend to the surface. This craft has a brief operational window of only two hours to drill into the ground and vacuum up material. After securing the samples, the lander will launch back into space from Phobos. Before departing Mars’s orbit in November 2030, the spacecraft is scheduled to conduct several flybys of Deimos, the smaller of the two moons. This comprehensive approach aims to maximize scientific return while managing the risks associated with landing on such a small celestial body.
The scientific community views this mission as a critical opportunity to address fundamental questions about the solar system’s history. Two primary theories exist regarding the origin of Phobos and Deimos. The giant impact hypothesis suggests that these moons formed from debris after a large celestial body collided with Mars. Alternatively, the capture hypothesis proposes that they are asteroids that were drawn into Mars’s gravitational field. Determining which scenario is correct could provide valuable clues about how habitable environments developed on terrestrial planets, including Earth.
Researchers believe that analyzing Martian material brought back from Phobos may shed light on the origins of life itself. By studying the composition of these samples, scientists hope to understand the conditions that allowed life to emerge on our planet. The data gathered will also inform future exploration efforts, particularly those involving human expeditions to Mars. Understanding the environment and resources available on the moons could be essential for planning sustained presence in the Martian system.
This Japanese-led effort unfolds against a backdrop of intense global competition in space exploration. While NASA has successfully landed nine spacecraft on Mars over the past fifty years, and China achieved a surface landing in 2021, no nation has yet attempted to sample the moons. The United States and China are currently engaged in a race to return rock samples from the Martian surface itself. NASA’s Perseverance rover has already collected such samples, but their return to Earth was paused following a congressional vote earlier this year.
China plans to launch its Tianwen-3 spacecraft around 2028, with the potential to bring back Mars samples as early as 2031. This timeline overlaps with the expected return of the Japanese mission from Phobos. Despite the competitive landscape, experts emphasize the unique value of studying the moons rather than just the planet. Tom Statler, an astrophysicist at NASA involved in the project, described the atmosphere as filled with excitement and adrenaline. Markus Grebenstein, chief of the German Space Agency’s rover team, called it a once-in-a-lifetime chance to participate in the first sample return mission from the Martian system.
As the spacecraft begins its journey toward Mars, the focus shifts to ensuring the successful execution of each complex phase. From the initial orbit insertion to the delicate landing operations, every step must proceed according to plan. The success of this mission could redefine our understanding of planetary formation and set new standards for international collaboration in space. With thousands of spectators watching the launch via livestream, the event underscored the enduring public fascination with exploring the cosmos and uncovering the mysteries of our solar system.
Sources behind this briefing
Go to the original reporting
- The Guardian US↗‘Once-in-a-lifetime chance’: Japan launches historic mission to collect rocks from Mars’s moon Phobos
