Japan has launched a spacecraft on a first-of-its-kind journey to Mars, where it will try to land on the planet’s moon Phobos and bring a piece of it back to Earth.
The Japan Aerospace Exploration Agency, which is leading the effort, launched the spacecraft before dawn on Tuesday from the main spaceport on Tanegashima Island, with officials declaring success an hour later, when the spacecraft separated as planned from the rocket’s upper stage.
Flight controllers burst into applause, shaking hands and embracing each other.
Five space agencies are backing the five-year mission, which will put a robotic sample collector and a small rover on Phobos, the larger and nearer of Mars’ two tiny moons.
A first for Mars and its moons
The $578 million mission, known as MMX for Martian Moon Exploration, centres on a 5-tonne spacecraft expected to reach Mars by late next summer. It will match Phobos’ tight orbit before releasing Idefix, a French-German rover named after the white terrier in the Asterix comics.
No bigger than a microwave oven, Idefix will drop onto Phobos on its own, bouncing for several minutes before stopping in the moon’s extremely low gravity.
“There’s a lot of adrenaline and a lot of excitement and a lot of wow,” said NASA astrophysicist Tom Statler, who is involved in the project.
NASA has landed nine spacecraft on Mars over the past 50 years, and China touched down in 2021, but no one has ever ventured onto Phobos or its companion, Deimos, and no one has returned samples from Mars, let alone its moons. If successful, dust, soil and rock from Phobos will reach Earth in 2031.
Analysts believe Japan has an edge, having already completed two asteroid sample returns.
Phobos is a lumpy, potato-shaped rock about 22 kilometres across. Studying it could explain how Mars’ moons, and possibly moons elsewhere, formed.
What happens after Idefix the rover lands?
The four-wheeled rover is designed to right itself if it lands upside down. All bets are off, though, if it sinks into soft soil or gets wedged between rocks, said the French Space Agency’s Julien Baroukh. Once the rover’s solar panels are deployed, the vehicle can no longer right itself, he added, which is why it will move at a glacial 1 millimetre per second (0.04 inches per second).
Idefix will serve as a “scout for safety,” according to Baroukh, as it prowls around Phobos for 100 days. Japanese flight controllers want to avoid powdery soil and rough terrain when the mothership — a four-legged stationary lander — descends to the surface to gather samples in late 2028 or 2029.
The lander will spend just two hours on Phobos, drilling and vacuuming up at least 10 grams (one-third of an ounce) of material before launching back into space. It will then study Deimos during a series of flybys, leave the Martian neighbourhood in 2030 and hurry back to Earth to deliver the samples in the Australian desert in 2031.
It is a treacherous undertaking, with wreckage littering the path. The moons’ names are hardly comforting: Phobos is Greek for 'fear', and Deimos means 'dread'. They are the twin sons of Ares, the god of war, known as Mars in Roman mythology.
Scientists hope to learn how Mars’ two moons formed
Russia failed in all three of its Phobos attempts, as well as in many other Mars endeavours. In its only other Mars mission, Japan failed to get a spacecraft into orbit around the red planet. Even NASA has had its share of flops in the quest to answer the burning question: did life ever exist on Mars?
By studying the moons, scientists hope to learn whether Phobos and Deimos formed in the aftermath of an ancient collision between Mars and a battering space rock. The moons might also be stray asteroids that were captured by Mars’ gravity.
Either way, scientists expect to find traces of Mars on Phobos, making the samples an irresistible two-for-one that should help demystify how planets and moons form, and perhaps even the recipe for life. The findings will help shape future Mars missions, including crewed ones, said Lindsay Hays, NASA’s acting planetary science director.
“It is a once-in-a-lifetime chance. We are part of the first sample return mission from the Martian system,” said Markus Grebenstein, the German Space Agency’s rover chief.
Japan is not alone in seeking the scientific riches in the Martian system’s rocks and dirt. China plans to launch its own Mars sample return mission in 2028. NASA, meanwhile, is still debating how to retrieve the more than 30 sample tubes collected by its Perseverance rover, the new champion of off-Earth driving.
Japan and China could end up neck and neck in returning samples from the Martian system, as both are targeting 2031.
Japan is investing $350 million (€308 million) in this mission. NASA is contributing $87 million (€77 million), the French Space Agency about $68 million (€60 million), the German Space Agency about $56 million (€49 million) and the European Space Agency some $17 million (€15 million).