Japan’s Most High-Profile Astronauts

August 8, 2025, marks a significant milestone in Japan’s space exploration history. Forty years ago, the country nominated its first astronaut candidates: Takao Doi, Mamoru Mohri, and Chiaki Mukai. To commemorate this anniversary, we profile seven of Japan’s most notable astronauts, highlighting their achievements and contributions to space exploration.

• Toyohiro Akiyama: First Japanese in space, a unique journey from TV to space.
• Mamoru Mohri: Japan’s first professional astronaut, known for his educational outreach.
• Chiaki Mukai: First Japanese woman in space, a pioneer in life sciences experiments.
• Takao Doi: First Japanese astronaut to perform a spacewalk, known for his unique experiments.
• Koichi Wakata: Most experienced Japanese astronaut, who commanded the ISS.
• Soichi Noguchi: Notable for his multiple missions and contributions to international space collaboration.
• Akihiko Hoshide: A distinguished astronaut and spacecraft commander with numerous missions.

Toyohiro Akiyama: The Unexpected Astronaut

Toyohiro Akiyama’s journey to becoming the first Japanese person in space is anything but conventional. A former TV correspondent for TBS, Akiyama was selected for the Soyuz TM-11 mission to the Russian space station Mir in 1990. He was not a trained astronaut but was chosen to boost TBS’s ratings, reflecting a unique approach to space exploration.

Despite his lack of scientific training, Akiyama underwent rigorous training for over a year, even quitting his four-pack-a-day smoking habit. His flight in December 1990 was marked by significant media attention, but it was also challenging; Akiyama reportedly struggled with space sickness. His experience paved the way for future astronauts and showcased the potential for non-traditional candidates in space missions.

Mamoru Mohri: The First Professional Astronaut

Mamoru Mohri holds the distinction of being Japan’s first professional astronaut. Born in Hokkaido, he flew aboard the Space Shuttle Endeavour during the STS-47 mission in 1992 as the chief payload specialist for Spacelab-J. This mission included a diverse crew, among them Mae Jemison, the first African-American woman in space.

During his mission, Mohri conducted experiments that were broadcasted to students in Japan, aiming to inspire future generations. He honored the memory of Christa McAuliffe, a teacher who tragically lost her life in the Challenger disaster, by engaging students in science education. Mohri’s contributions to space science continued with his second flight on STS-99, marking him as a significant figure in Japan’s space history.

Chiaki Mukai: A Trailblazer for Women in Space

Chiaki Mukai’s journey to becoming the first Japanese woman in space began with her background in medicine. After being inspired by early astronauts, she was selected as a backup astronaut in 1988 and later flew on the STS-65 mission in 1994. Her work focused on life sciences and space medicine, demonstrating the importance of these fields in space exploration.

In 1998, Mukai flew again on the STS-95 mission, where she became the first Japanese citizen to travel to space twice. Throughout her missions, she spent a total of 23 days in space, conducting valuable research that contributed to our understanding of human health in microgravity. Mukai’s achievements have inspired many women in science and engineering, highlighting the importance of diversity in space exploration.

Takao Doi: The Spacewalker

Takao Doi is notable for being the first Japanese astronaut to perform an Extravehicular Activity (EVA), or spacewalk. His first mission was the STS-87 mission aboard the Space Shuttle Columbia in 1997, where he participated in two spacewalks totaling over 12 hours. Doi’s experiments included capturing a malfunctioning satellite, showcasing the hands-on problem-solving required in space.

On his second mission, STS-123 in 2008, Doi conducted a unique experiment involving a boomerang sent to space by a world champion. His experiences and experiments have contributed significantly to our understanding of both the physical and psychological challenges of space travel. Doi’s career reflects the diverse roles astronauts can play in advancing space science and technology.

Koichi Wakata: The Veteran Astronaut

With a remarkable total of 504 days spent in space across five missions, Koichi Wakata is Japan’s most experienced astronaut. His first flight was on the STS-72 mission in 1996, where he operated the robotic arm to retrieve a satellite. Wakata’s long career includes significant milestones, such as commanding the International Space Station (ISS) during Expedition 39, making him the first Japanese to do so.

Wakata’s leadership in space missions has been pivotal, especially during his 188 consecutive days in space from November 2013 to May 2014. He has often expressed a sense of responsibility to represent Japan in space, contributing to international cooperation in space exploration.

Soichi Noguchi: A Global Ambassador in Space

Soichi Noguchi is known for his contributions to multiple space missions and his role as a global ambassador for space exploration. He flew on the STS-114 mission in 2005, which was a critical return-to-flight mission following the Columbia disaster. His experience also includes a long-duration stay on the ISS, where he conducted various scientific experiments.

Noguchi’s work emphasizes the importance of international collaboration in space. He has participated in numerous joint missions, fostering relationships between Japan and other spacefaring nations. His efforts to communicate the wonders of space to the public have made him a beloved figure in Japan and beyond.

Akihiko Hoshide: A Leader in Space Exploration

Akihiko Hoshide has made significant contributions to space exploration through his participation in several critical missions. His first flight was on the STS-124 mission in 2008, where he helped deliver the Japanese Kibo laboratory to the ISS. Hoshide is known for his work on various experiments and technology demonstrations aboard the ISS.

Hoshide’s leadership qualities were highlighted during his command of the ISS during Expedition 32. He has been involved in various outreach activities, inspiring the next generation of scientists and engineers in Japan and around the world. Hoshide’s dedication to science and education reflects the broader mission of astronauts to advance human knowledge and inspire future exploration.

Reader Q&A

What inspired Japan to nominate its first astronauts?
Japan’s nomination of its first astronauts in 1985 was part of a broader strategy to engage in international space exploration and enhance its scientific capabilities.

How do Japanese astronauts contribute to international missions?
Japanese astronauts participate in various international missions, collaborating with agencies like NASA and ESA, and conducting experiments that benefit global scientific knowledge.

What are some key achievements of Japanese astronauts?
Japanese astronauts have made significant contributions, including pioneering spacewalks, conducting life sciences research, and representing Japan in international space leadership roles.