The following is a list of characters for the Japanese manga series by Chūya Koyama, Space Brothers, which has been adapted into an anime television series and a live-action film.

Main characters

Portrayal Shun Oguri (film), Hiroaki Hirata (anime), Miyuki Sawashiro (anime, young) The elder Nanba brother who was born on October 28, 1993, when Japan lost the 1994 FIFA World Cup qualification match in Qatar. He has always wanted to stay a step ahead of his younger brother, but ran into trouble after getting fired from his job, for head butting his boss like Zinedine Zidane did to Marco Materazzi in the 2006 FIFA World Cup Final. After Hibito asked their mother to send in his astronaut application to JAXA, he is chosen to join their astronaut recruitment program and overcomes hardships of JAXA's continuous tests.

Portrayal Masaki Okada (film), Kenn (anime), Yūko Sanpei (anime, young) The younger Nanba brother who was born on September 17, 1996, when Hideo Nomo pitches a no-hitter against the Colorado Rockies, leading the Los Angeles Dodgers to a 9-0 victory in Major League Baseball. He is currently the first Japanese astronaut preparing to go on a lunar landing, thus achieving the brothers' childhood dream. He is supportive of Mutta.

Portrayal Kumiko Asō (film), Miyuki Sawashiro (anime) One of Mutta's fellow applicants in the astronaut program, who he has a huge crush on. When young, her father developed amyotrophic lateral sclerosis (ALS) which could not be cured at the time. After he died, Serika became motivated to become an astronaut and develop new cures for rare diseases and illnesses aboard the International Space Station.

Portrayal Yoshio Inoue (film), Masayuki Katō (anime) One of Mutta's fellow applicants in the astronaut program. He resides with his wife and daughter. He is good at guessing people's ages and Mutta's close friend.

Portrayal Miyuki Sawashiro (anime) Hibito's pet pug he has while in Houston, named after the Apollo program.

Supporting characters

Voiced by Masako Ikeda Sharon is an aerospace scientist, who does research by using a telescope to look up into space. She is a mentor to Mutta and Hibito when they were young. She taught them many things such as English and many life lessons. Mutta and Hibito still look to her for their problems and they share a very close relationship. Her dream is to build a lunar telescope on the moon.

Voiced by Mariko Hayashi Tamura works with Sharon as an assistant who also does research using a telescope.

Voiced by Mayumi Tanaka She is the mother of Hibito and Mutta. She is a very caring and enthusiastic person.

Voiced by Chō He is the father of Hibito and Mutta. He has fun doing various impersonations and voices.

Voiced by Tadashi Nakamura He is a middle-aged man who enjoys casual gambling and is friends with Hibito in Houston. He and his wife helps walk Hibito's dog Apo.

Voiced by Tamaki Taura She is a middle-aged woman and Ozzy Smith's wife.

Voiced by Show Ryuzanji He is an employee at JAXA who initially wanted to become an astronaut but wasn't lucky enough. He inspired Mutta and Hibito when they were young and is fascinated by Mutta. He personally interviewed Mutta's colleagues about the headbutting incident when the issue was raised by JAXA's selection committee.

Voiced by Yuko Tachibana She is Mutta's guide around NASA when he visits. She is very talkative and is knowledgeable of NASA and astronaut training and gave Mutta many tips.

Voiced by Toa Yukinari She is an aspiring astronaut who becomes friends with Serika during the examination process. She drops out after the second exam.

Voiced by Takanori Hoshino He was one of Mutta's fellow applicants in the astronaut program and one of the few that passed the third exam. Nitta was in the same "A" team as Mutta during the third exam. He is a sharp, smart and a calm man. He studied sports medicine at the University of Tsukaba and he also enjoys playing kendo.

Voiced by Ryo Naito He was one of Mutta's fellow applicants in the astronaut program and was in the same "A" team as Mutta during the third exam. He is a biology student from Kyoto. He is a young man with a quick temper and is often quick to point out errors and has no problem speaking his mind.

Voiced by Naoki Bandō He was one of Mutta's fellow applicants in the astronaut program and was in the same "A" team as Mutta during the third exam. He is a middle-aged man who worked on rocket development. He is following his dreams after "losing" his daughter when he was an absent father due to his rocket work. He is friendly and talkative.

Voiced by Yutaka Aoyama He is the director at JAXA. He is rather quirky and upbeat and is very much interested in Mutta. His name is a play on NASDA, one of JAXA's predecessor agencies, and his character design is based on Chiaki Mukai's husband Dr. Makio Mukai.

Voiced by Eiji Ito He is a JAXA staff member who helps manage the third exam. He is strict and to the point.

Voiced by Shintaro Asanuma One of Mutta's fellow applicants in the astronaut program and was in the same "B" team as Kenji during the third exam. He was one of the few that passed the third exam.

Voiced by Yuko Sanpei One of Mutta's fellow applicants in the astronaut program and was in the same "B" team as Kenji during the third exam. She was one of the few that passed the third exam.

Voiced by Shigeyuki Susaki One of Mutta's fellow applicants in the astronaut program and was in the same "B" team as Kenji during the third exam. He is smart and spends a lot of time playing with a Rubik's cube that he carries around. He is rather shy and is the youngest member of Team B.

Voiced by Masayasu Nagata One of Mutta's fellow applicants in the astronaut program and was in the same "B" team as Kenji during the third exam. He was one of the few that passed the third exam. However since the start of the exam he has been very nervous and can usually be seen shaking his leg or looking worried. He joined the program because his father wanted him to become an astronaut. He is named after Soviet Union astronaut Yuri Gagarin. He has a huge interest on extra-terrestrial life forms research.

Voiced by Takeshi Ohba One of Mutta's fellow applicants in the astronaut program and was in the "C" team during the third exam. He is very athletic and is often seen with Yamato.

Voiced by Ryosuke Sakamaki He is an American astronaut, who likes Japanese things like sushi. He is Hibito's backup on the upcoming mission to the moon.

Voiced by Kenji Nomura He is an astronaut at JAXA. He is the Japanese astronaut who has spent the most time working in space, having done several missions on the ISS. It seems that he has a grudge against Hibito for being chosen over him to go on an upcoming lunar landing mission.

Portrayal Taro Ishida (anime), Buzz Aldrin (film) NASA's eccentric veteran flight trainer that enjoys Ice Breakers Sours. In the live action movie his role is taken by Buzz Aldrin.

References