The Japan Aerospace Exploration Agency (JAXA) is Japan's national space agency, formed on October 1, 2003. Its Hayabusa probes performed the world's first asteroid sample returns, in 2010 and 2020, its SLIM spacecraft landed about 55 meters from its lunar target in January 2024,[4] and its MMX mission, planned for launch in late 2026, aims to bring back the first samples from the Martian moon Phobos.[1][2]
JAXA was created by merging the Institute of Space and Astronautical Science (ISAS), the National Aerospace Laboratory, and the National Space Development Agency, and is headquartered in Chofu, Tokyo, with Hiroshi Yamakawa as president. The agency conducts science missions, human spaceflight, and launch vehicle development, flying its largest rockets from the Tanegashima Space Center in southern Japan, and it has specialized in missions that return extraterrestrial material and in precision spacecraft engineering. It is also a core partner on the International Space Station, where its new HTV-X freighter made its first delivery in 2025.[3]
SLIM and lunar exploration
The Smart Lander for Investigating Moon (SLIM) launched in September 2023, sharing its rocket with the XRISM X-ray telescope that JAXA developed with NASA and ESA, and touched down on January 20, 2024 (Japan time), making Japan the fifth country to soft-land on the Moon. The mission's purpose was accuracy rather than endurance: JAXA assessed that SLIM's vision-based navigation achieved its pinpoint landing goal, coming down about 55 meters east of the original target, and within roughly 10 meters of the point it selected during final descent, despite losing one of its two main engine nozzles on the way down.[4]
The nozzle failure left the lander tipped nose-down, with its solar cells facing away from the Sun, yet SLIM still returned data, observed surrounding rocks in ten spectral bands, and survived three lunar nights it was never designed to endure. JAXA declared the mission complete in August 2024 after months of silence.[4]
Japan's next lunar surface project is the Lunar Polar Exploration mission (LUPEX), a joint rover mission with India's ISRO that the two agencies formalized in an implementing arrangement signed during the India-Japan summit on August 29, 2025. JAXA is responsible for the rover, a 350-kilogram vehicle carrying a 1.5-meter drill, and for the H3 rocket that will launch the mission no earlier than 2028; ISRO builds the lander, and India counts the flight as Chandrayaan-5. The rover will prospect for water ice in the permanently shadowed terrain of the lunar south pole with instruments from Japan, India, NASA, and ESA.[5][6]
JAXA also participates in the Artemis program. Under an implementing arrangement signed with NASA in April 2024, Japan will develop a pressurized rover in which astronauts can drive across the lunar surface without spacesuits, and NASA will fly two Japanese astronauts to the Moon's surface; the two governments have stated a shared goal of making a Japanese astronaut the first non-American to walk on the Moon.[7]
Hayabusa asteroid sample returns
JAXA's Hayabusa probe launched in 2003, reached the asteroid Itokawa in 2005, and in June 2010 delivered the first samples ever collected from an asteroid, despite fuel leaks, failed reaction wheels, and a damaged sampler. Hayabusa2 followed in 2014 with a more ambitious plan at the carbon-rich asteroid Ryugu: it fired a copper impactor to expose subsurface material, collected two samples, and returned 5.4 grams to Australia in December 2020. Analysis of the Ryugu grains found amino acids and other organic compounds, informing theories about the delivery of water and organics to early Earth.
| Mission | Launched | Target asteroid | Samples returned |
|---|---|---|---|
| Hayabusa | 2003 | Itokawa | June 2010, the first asteroid samples ever collected |
| Hayabusa2 | 2014 | Ryugu | December 2020, 5.4 grams |
Hayabusa2's extended mission recorded its first asteroid encounter on July 5, 2026, when the spacecraft flew past Torifune (2001 CC21), an elongated body about 840 meters on its long axis, at roughly 400 meters above its surface, the closest flyby of any Solar System body to date, missing its aim point by only 120 meters.[8] The spacecraft also performed the first laser ranging of an asteroid during a flyby, and JAXA presented the guidance precision as a planetary defense demonstration, since the same control could steer a spacecraft into a hazardous asteroid.[9] The cruise continues toward 1998 KY26, a roughly 11-meter asteroid that spins once every five minutes, with arrival planned for 2031.[10]
JAXA's planetary defense cooperation with ESA deepened in May 2026, when the two agencies signed a cooperation memorandum and JAXA agreed to supply solar array wings, a thermal infrared imager, and an H3 launch for ESA's RAMSES mission, due to launch in 2028 to observe the asteroid Apophis around its close Earth approach in 2029.[11]
H3 and launch vehicles
The H3, developed with Mitsubishi Heavy Industries, is Japan's new flagship rocket, replacing the H-IIA, which retired in June 2025 after 50 flights.[12] H3's debut in March 2023 failed when the second stage did not ignite, but the vehicle recovered with a string of successes from February 2024 onward, lofting payloads that included navigation and Earth observation satellites and the first HTV-X.[13][14]
| H3 configuration | First stage engines | Solid boosters | First flight |
|---|---|---|---|
| H3-22S/22L | 2 x LE-9 | 2 | March 2023 (22S) |
| H3-24L/24W | 2 x LE-9 | 4 | October 2025 (24W) |
| H3-30S | 3 x LE-9 | 0 | June 2026 |
A second failure came on December 22, 2025, when an H3-22S on the rocket's eighth flight lost the Michibiki No. 5 navigation satellite after the second stage shut down early during its second engine burn.[15] Investigators traced the fault to the satellite adapter, which broke apart under unusual shocks at payload fairing separation; falling debris punctured the second stage's liquid hydrogen lines.[14] The rocket returned to flight on June 12, 2026, with the first all-liquid H3-30 configuration, which placed six small satellites into a 580-kilometer orbit.[16][17] The ninth flight, carrying the Michibiki No. 7 navigation satellite, launched successfully from Tanegashima on August 11, 2026, bringing the H3's record to seven successes in nine flights; a second HTV-X cargo flight and the MMX launch are also planned before the end of the year.[14][18][33]
JAXA is separately developing the small solid-fuel Epsilon S, whose second-stage motor exploded during ground tests in July 2023 and November 2024.[19] The agency set the troubled new motor aside in favor of an improved version of an older, proven design, accepting a lower payload target, and reported a successful roughly two-minute static firing of the reworked stage at Tanegashima on July 23, 2026; it aims to fly a demonstration vehicle by the end of March 2027.[20]
MMX Phobos sample return
Martian Moons eXploration (MMX) is JAXA's next flagship science mission, a sample return targeting the Martian moon Phobos. The spacecraft was shipped from Kamakura and delivered to Tanegashima on March 31, 2026, for a planned launch on an H3 in the late-2026 window, around November, reaching Mars orbit in 2027.[2][21] MMX will spend about three years studying Phobos and Deimos, land on Phobos at least once to collect more than 10 grams of surface material, and deploy a small rover built by the French and German space agencies. Its instruments include MEGANE, a gamma-ray and neutron spectrometer contributed by NASA. The return module is scheduled to bring the samples to Earth in Japanese fiscal year 2031, which would be the first material ever returned from the Martian system, and should settle whether Phobos is a captured asteroid or debris from a giant impact on Mars.[2][22]
BepiColombo and Mercury
BepiColombo, a Mercury mission that JAXA flies jointly with ESA, launched in October 2018 and carries two orbiters: ESA's Mercury Planetary Orbiter and JAXA's Mio, which will study the planet's magnetic field and magnetosphere. A power problem in the transfer module's ion propulsion system, found in 2024, forced a slower trajectory and pushed the arrival back by about a year; in May 2026 JAXA announced that BepiColombo will enter orbit around Mercury on November 21, 2026, with Mio due to separate from the transfer module that December to begin observations.[23][24]
ISS contributions and human spaceflight
JAXA supplied the International Space Station's largest laboratory, Kibo, launched across 2008-2009, and resupplied the outpost with nine HTV "Kounotori" freighters between 2009 and 2020. Its successor, HTV-X, is larger and can keep payloads powered until berthing. HTV-X1 launched on an H3 on October 26, 2025, carrying about 5.8 tonnes of supplies, and was captured by JAXA astronaut Kimiya Yui with the station's robotic arm four days later.[3][25] After just over four months berthed to the station, it departed on March 7, 2026, spent two and a half months flying free for technology demonstrations, and ended its mission with a controlled destructive reentry over the Pacific on May 26, 2026 (Japan time).[26]
Japanese astronauts fly regularly on station crews, launching in recent years on Commercial Crew Program flights: Takuya Onishi commanded the ISS in 2025, only the third Japanese astronaut to do so, and Kimiya Yui logged 166 days on his second station mission from August 2025 to January 2026.[27][28] JAXA had committed hardware to the lunar Gateway program, including batteries for the HALO crew module plus the life support system, batteries, thermal control, and cameras for the I-Hab habitat, along with a Gateway resupply mission flown by an upgraded HTV-XG freighter.[29][30] Those plans are in question after NASA paused Gateway in its current form in March 2026 and issued a stop-work order the following month, a decision that leaves Japan's contributions to the reshaped Artemis program to be renegotiated.[32] The agency selected two new astronauts in 2023, its first class in 14 years; Makoto Suwa and Ayu Yoneda were certified in October 2024 and are training with lunar missions in view.[31]
References
- SLIM, Japan's precision lunar lander - The Planetary Society.
- Martian Moons eXploration - JAXA.
- Launch Result of New unmanned cargo transfer spacecraft1 (HTV-X1) aboard the 7th H3 Launch Vehicle (H3 F7) - JAXA.
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- Lunar Polar Exploration (LUPEX) - JAXA Human Spaceflight Technology Directorate.
- PM Modi welcomes ISRO-JAXA collaboration for Chandrayaan-5 LUPEX mission - DD News.
- NASA and Japanese Government sign the Implementing Arrangement concerning Lunar Surface Exploration using the Pressurized Rover - JAXA Space Exploration Center.
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- Asteroid explorer Hayabusa2 achieves world-first laser ranging during asteroid flyby - JAXA.
- Asteroid Explorer Hayabusa2 - JAXA ISAS.
- JAXA and ESA Conclude Memorandum of Cooperation on Planetary Defence and Sign Cooperation Agreement on the RAMSES Asteroid Apophis Mission - JAXA.
- Final H-2A launches Earth science satellite - SpaceNews.
- H3 Launch Vehicle - JAXA.
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- Launch Failure of the 8th H3 Launch Vehicle and Setting up a Special Task Force - JAXA.
- Japan's space agency to launch H3 rocket on June 10 - The Japan Times.
- Launch Result of H3 Launch Vehicle flight No.6, 30 configuration Test Vehicle - JAXA.
- Launch time and Launch window of MICHIBIKI No. 7, Quasi-Zenith Satellite System (QZS-7) aboard H3 Launch Vehicle flight No.9 - JAXA.
- Establishment of the Investigation Team for the Combustion Anomaly during the Static Firing Test of the Epsilon S Second-Stage Motor - JAXA.
- Japan conducts rocket engine combustion test after lowering payload target - Xinhua.
- The Martian Moons eXploration (MMX) spacecraft has successfully been delivered to the JAXA Tanegashima Space Center - JAXA ISAS.
- MMX factsheet - ESA.
- Change in arrival time for the international Mercury exploration mission, BepiColombo - JAXA ISAS.
- Japanese Space Agency names arrival date for BepiColombo Mercury mission - The Register.
- Successful berthing of the HTV-X1 to the International Space Station (ISS) - JAXA.
- Successful Controlled Re-entry of HTV-X1 - JAXA.
- ONISHI Takuya - JAXA Human Spaceflight Technology Directorate.
- Return of Crew Dragon Spacecraft (Crew-11) with JAXA Astronaut YUI Kimiya - JAXA.
- NASA, Government of Japan Formalize Gateway Partnership for Artemis Program - NASA.
- NASA, Japan Announce Gateway Contributions, Space Station Extension - NASA.
- Japan's lunar ambitions advance with two new astronauts - The Japan Times.
- NASA outlines ambitious $20 billion plan for moon base - Spaceflight Now, March 25, 2026.
- Japan successfully launches H3 rocket with Michibiki satellite - The Japan Times, August 11, 2026.

