Japan’s Mini Moon Rover Is Basically a Pokémon Ball

It will start the journey as a ball, then split into two wheels to roam the moon.
The Pokéball-like robot will be sent to the moon in 2022. Photos: JAXA / TOMY / SONY / Doshisha University (left); Luis Acosta / AFP

In its efforts to build a crewed lunar rover in less than a decade, Japan is quite literally getting the ball rolling. 

The country is aiming to get a moon rover ready by 2029 for crewed missions, and has developed a spherical robot to be sent to the moon next year to survey the lunar surface.

The ultra-compact ball weighs about half a pound and measures 3.1 inches in diameter, about the size of a baseball—or a Pokéball.


It will start its trip as a ball, then pop open into “running form” upon arrival, the Japan Aerospace Exploration Agency (JAXA) said on Thursday. It will split itself into two halves, each functioning as a wheel so the robot can roam about the lunar surface.


The baseball-sized robot can transform itself into two wheels for movement. Image: Courtesy of JAXA / TOMY / SONY / Doshisha University

It also has a camera for sending back images and will analyze moon dust, the sharp and abrasive material known to cause “lunar hay fever.” Photos taken during the robot’s expedition will be beamed back to Earth via the moon lander.

To develop this ultra-lightweight robot, JAXA borrowed the miniaturization technologies of Tomy, a Japanese toy company, and the Doshisha University in Kyoto. The technology giant Sony is responsible for the control mechanics. 

The robot will ride on a lunar lander from ispace, the Japanese company in charge of the robot’s voyage to the moon. The 2022 mission will also deliver a bigger robotic rover developed by the United Arab Emirates.

JAXA hopes that the information collected by the robo-ball about the moon’s gravity and its surface conditions will help it develop the autonomous driving and cruising technology for the crewed RV-like rover. Japanese carmaker Toyota is jointly manufacturing rover prototypes.


JAXA and Toyota are developing a crewed pressurized lunar rover named the Lunar Cruiser. Image: courtesy of Toyota

If the 2022 mission succeeds, Japan and the UAE will join the ranks of the former Soviet Union, the U.S., and China as countries that have soft-landed a spacecraft on the moon. The UAE will also be the first country from the Arab world to explore the moon.


In 2013, Japan became the first country to launch a robotic astronaut, Kirobo, to the International Space Station. Four years later, it put a self-propelled ball camera, called the Int-Ball, on the space station to help document the work of astronauts on board.

A commercial lunar mission funded by Japanese billionaire Yusaku Maezawa is set to bring tourists around the moon on SpaceX’s Starship spacecraft in 2023. The travelers will include Maezawa himself and eight chosen members of the public.

Japan is partnering with NASA in its Artemis Program, which plans to land the first woman and the next man on the moon by 2024, as well as start construction of a lunar base camp by 2028.

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