Reaching for the Moon: Japan’s Team Hakuto Competes in International Lunar Race

Science Technology

The Google Lunar XPrize competition pits the technical prowess of teams from around the world in a race to successfully land a privately funded rover on the moon. Among the competitors in the global contest sponsored by Internet giant Google is Japanese team Hakuto. The Tokyo-based crew is considered to be a major contender after winning a Milestone Prize in the competition in 2015. Hakuto’s rover is expected to launch in the latter half of 2016 or in 2017, and will arrive on the lunar surface aboard the same lander as rovers created by Chilean and US teams.

The Mission: Land, Travel, Broadcast from the Moon

The Google Lunar XPrize was created in 2007 by the US nonprofit X Prize Foundation to spark the growth of the space industry. The goal of the teams is to meet three mission requirements by the end of 2017: land a rover developed with private funds on the moon, move the rover on autopilot for a distance of at least 500 meters along the lunar surface, and transmit high-definition still and video images of the lunar environs back to Earth.

The first team to complete the mission will win $20 million in prize money, and the runner-up will receive $5 million. An additional purse of $4 million has been set aside for bonus prizes.

As of March 2016, 16 teams representing 13 countries remained in the race. Five of the teams are considered within reach of the top prizes: Astrobotic and Moon Express of the United States, Indus of India, Part-Time Scientists of Germany, and Hakuto. In January 2015 X Prize awarded Milestone Prizes totaling $5.25 million to these teams for demonstrating key technologies in the three areas of landing (ability for a soft landing on the moon), mobility (rover’s ability to navigate the lunar surface), and imagery (ability to transmit images back to Earth). Hakuto received a $500,000 Mobility Milestone Prize for its micro-rovers.

Astrobotic, meanwhile, won Mobility Prizes in all three areas, making it the top contender for the Grand Prize.

The Faces of the Team

Hakamada Takeshi, team leader of Hakuto. (Photo by Ōtani Kiyohide)

Hakuto, which literally means “white rabbit,” derives its name from a Japanese legend of a rabbit living on the moon. Team leader Hakamada Takeshi has aspired to the stars since becoming enchanted by the Star Wars movies as a young boy. He first studied aerospace engineering at Nagoya University and then went on to earn his master’s degree at the Georgia Institute of Technology.

Hakamada initially joined the race as a volunteer in a mixed Japanese-European team. When the European members backed out in 2013, Hakamada launched Hakuto. In May 2013 he set up the company Ispace Inc. in Tokyo as the operational backbone of Hakuto, and the team went into high gear. Development of the rovers is led by Professor Yoshida Kazuya of Tōhoku University, who was involved in the successful round-trip mission of the Japan Aerospace Exploration Agency’s asteroid explorer Hayabusa.

Micro-Rovers Packed with Technology

Hakuto developed two rovers, the four-wheeled Moonraker and two-wheeled Tetris. Both are smaller than the rovers of the other teams, reflecting Japan’s strength in miniaturization and helping the team qualify for the Milestone Prize.

Hakamada explains that for financial reasons, only Moonraker will head for the moon. The flight model—the model that will actually be sent to the moon—will be similar in size to the current model, but the team aims to pare down the weight from 7 to 4 kilograms. Hakamada hopes to put Tetris into action in a future resource exploration mission by Ispace.

PFM3, a preflight model of the four-wheeled Moonraker, is 60 cm long, 54 cm wide, and 48 cm tall. (Photo by Nagasawa Takaaki)

The PRM3 model of the supercompact Tetris weighs in at only 2 kg and measures 54 cm by 27 cm by 21 cm. (Photo by Nagasawa Takaaki)

Moonraker’s body is composed of carbon-fiber-reinforced plastic. The wheels, made of highly heat-resistant Ultem resin, have grousers to provide traction on the powdery regolith that covers the lunar surface. The rover is installed with miniature cameras facing four directions, as well as a simultaneous localization and mapping system that enables it to estimate its location and map its surroundings at the same time.

Temperatures on the moon are extreme, ranging from over 100 degrees Celsius during the day to 150 degrees below zero at night. Radiation levels are also high. In addition to being sandy, the lunar surface has craters and rocks. The technological challenges to completing the mission under these harsh conditions are enormous, especially when the only electricity available is what is generated by solar panels installed on the rover.

Piggybacking on a Rival’s Lander

Hakuto does not have its own lander. In February 2015 it signed a ride-share contract with fellow contestant Astrobotic to load Moonraker on board the latter’s Griffin lander. The Chilean team’s rover will also be piggybacking on Griffin, meaning that the rovers of all three teams will leave Earth on the same rocket and be released on the lunar surface simultaneously after touchdown.

The launch of the Falcon 9 rocket of US company SpaceX, which will carry the lander into space, is fast approaching. “Hakuto has focused entirely on developing the rovers, so I believe that the three teams’ starting all at once increases our odds,” Hakamada says with confidence. Funding for development of the rovers and transport to the moon had been a concern, but thanks to the Milestone Prize the team has made great strides in raising the estimated ¥1 billion that it will need; aerospace leader IHI and telecommunications giant KDDI, among others, have signed on as partners.

The world waits in starry-eyed anticipation for the “mooncasts” that the rovers, if successful, will be sending back to Earth.

(Originally written in Japanese by Nagasawa Takaaki of the editorial department and published on March 31, 2016. Banner photo: The members of Team Hakuto, with Tōhoku University Professor Yoshida Kazuya at front row center. Photo courtesy of Hakuto.)

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