The Japan Aerospace Exploration Agency (JAXA) is the operator of the Japanese space program and Japan's national aeronautics research agency. It was formed in 2003 through the merger of the Institute of Space and Astronautical Science, the National Aerospace Laboratory of Japan, and the National Space Development Agency of Japan.
JAXA has conducted missions including the SELENE lunar orbiter, the SLIM lunar lander and rovers, and the Hayabusa asteroid missions. Hayabusa returned samples from an asteroid in 2010, while Hayabusa2 deployed rovers on an asteroid surface. Akatsuki studied Venus from orbit between 2015 and 2024. IKAROS tested solar sail propulsion in interplanetary space. BepiColombo, launched jointly with the European Space Agency in 2018, is a mission to Mercury. Martian Moons eXploration is scheduled to launch in December 2026 and is planned to return samples from Phobos.
JAXA operates the H3, a medium-lift launch vehicle, from Tanegashima Space Center and the Epsilon S, a small-lift launch vehicle, from Uchinoura Space Center. JAXA is one of five space agencies participating in the International Space Station (ISS) program. It developed Kibō, the station's largest module, and since 2009 has regularly resupplied the ISS using the HTV and later HTV-X cargo spacecraft. Since 1992, eleven members of the JAXA Astronaut Corps have flown aboard the Space Shuttle, Soyuz, and Dragon 2 spacecraft, primarily on missions to the ISS.
On 1 October 2003, three organizations were merged to form the new JAXA: Japan's Institute of Space and Astronautical Science (ISAS), the National Aerospace Laboratory of Japan (NAL), and National Space Development Agency of Japan (NASDA). JAXA was formed as an Independent Administrative Institution administered by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) and the Ministry of Internal Affairs and Communications (MIC).
Before the merger, ISAS was responsible for space and planetary research, while NAL was focused on aviation research. ISAS had been most successful in its space program in the field of X-ray astronomy during the 1980s and 1990s. Another successful area for Japan has been Very Long Baseline Interferometry (VLBI) with the HALCA mission. Additional success was achieved with solar observation and research of the magnetosphere, among other areas.
NASDA, which was founded on 1 October 1969, had developed rockets, satellites, and also built the Japanese Experiment Module. The old NASDA headquarters were located at the current site of the Tanegashima Space Center, on Tanegashima Island, 115 kilometers south of Kyūshū. NASDA was mostly active in the field of communication satellite technology. However, since the satellite market of Japan is completely open, the first time a Japanese company won a contract for a civilian communication satellite was in 2005. Another prime focus of the NASDA body is Earth climate observation. NASDA also trained the Japanese astronauts who flew with the US Space Shuttles.
The Basic Space Law was passed in 2008, and the jurisdictional authority of JAXA moved from MEXT to the Strategic Headquarters for Space Development (SHSD) in the Cabinet, led by the Prime Minister. In 2016, the National Space Policy Secretariat (NSPS) was set up by the Cabinet.
JAXA was awarded the Space Foundation's John L. "Jack" Swigert Jr., Award for Space Exploration in 2008.
Planning interplanetary research missions can take many years. Due to the lag time between these interplanetary events and mission planning time, opportunities to gain new knowledge about the cosmos might be lost. To prevent this, JAXA began commencing smaller and faster missions from 2010 onward.
In 2012, new legislation extended JAXA's remit from peaceful purposes only to include some military space development, such as missile early warning systems. Political control of JAXA passed from MEXT to the Prime Minister's Cabinet Office through a new Space Strategy Office.
In July 2026, JAXA and the National Space Agency of Singapore (NSAS) signed a memorandum of cooperation at SPACETIDE 2026 in Tokyo, the first bilateral space-agency agreement between Japan and Singapore. The agreement covers information exchange and cooperation in space technology and applications, space science and exploration, industry development, education, and policy and regulatory matters. The agencies also agreed to support business partnerships through JAXA's Co-funded Business Promotion Framework, under which Singapore became the third international partner after the United Kingdom and France.
Shūichirō Yamanouchi (2003–2004)
Hiroshi Yamakawa (2018–present)
As of 2026, JAXA operates the H3, a medium-lift launch vehicle, from Tanegashima Space Center and the Epsilon S, a small-lift launch vehicle, from Uchinoura. For experiments in the upper atmosphere JAXA uses the S-Series of sounding rockets.
Historically, Japan has also operated the H-I, H-II, H-IIA, H-IIB, J-I, N-I, N-II, and the Lambda and Mu rocket families.
Japan launched its first satellite, Ohsumi, in 1970, using ISAS' L-4S rocket. Prior to the merger, ISAS used small Mu rocket family of solid-fueled launch vehicles, while NASDA developed larger liquid-fueled launchers. In the beginning, NASDA used licensed American models.
The first model of liquid-fueled launch vehicle developed domestically in Japan was the H-II, introduced in 1994. NASDA developed the H-II with two goals in mind: to be able to launch satellites using only its own technology, such as the ISAS, and to dramatically improve its launch capability over previous licensed models. To achieve these two goals, a staged combustion cycle was adopted for the first stage engine, the LE-7. The combination of the liquid hydrogen two-stage combustion cycle first stage engine and solid rocket boosters was carried over to its successor, the H-IIA and H-IIB and became the basic configuration of Japan's liquid fuel launch vehicles for 30 years, from 1994 to 2024.
In 2003, JAXA was formed by merging Japan's three space agencies to streamline Japan's space program, and JAXA took over operations of the H-IIA liquid-fueled launch vehicle, the M-V solid-fuel launch vehicle, and several observation rockets from each agency. The H-IIA is a launch vehicle that improved reliability while reducing costs by making significant improvements to the H-II, and the M-V was the world's largest solid-fuel launch vehicle at the time.