December 3, 2014
On 3 December 2014, an H-IIA rocket climbed away from the cliffs of Tanegashima Space Center on Japan's southern coast, carrying a spacecraft built to finish what its predecessor had barely survived. The original Hayabusa had limped home in 2010, crippled and years late, with only micrograms of asteroid dust. Hayabusa2 was its redemption: sturdier ion engines, redundant systems, and a far more ambitious target, the carbon-rich asteroid 162173 Ryugu, a body thought to preserve water and organic chemistry from the Solar System's birth.
After three and a half years of patient ion-engine cruising, Hayabusa2 arrived at Ryugu on 27 June 2018 and found a spinning-top-shaped rubble pile roughly 900 metres across, strewn with boulders and almost nowhere safe to land. The team adapted. In September 2018 its MINERVA-II1 robots became the first rovers ever to move across an asteroid, hopping through the feeble gravity, and in October the German-French MASCOT lander worked for about 17 hours on the surface.
Then came the precision strikes. On 22 February 2019 Hayabusa2 swooped down, fired a projectile into the surface and caught the flying debris. That April it detonated a device that drove a copper impactor into Ryugu at around two kilometres per second, blasting open an artificial crater. On 11 July 2019 the spacecraft touched down again beside the wound and collected subsurface material never weathered by space, a first in exploration history.
On 6 December 2020 a capsule streaked like a fireball over Woomera, Australia, and was recovered in the desert that morning. Inside was 5.4 grams of Ryugu, 54 times the mission's 0.1-gram requirement, dark grains that laboratories found laced with amino acids and water-bearing minerals. The mothership never came home; it swung past Earth and is still flying an extended mission, with a flyby of asteroid 2001 CC21 in 2026 and a rendezvous with tiny, fast-spinning 1998 KY26 planned for 2031.
Launch
3 Dec 2014, H-IIA F26, Tanegashima
Spacecraft mass
~609 kg (fuelled)
Ryugu arrival
27 Jun 2018
Touchdowns
22 Feb 2019 and 11 Jul 2019
Sample returned
6 Dec 2020, Woomera, Australia
Sample mass
5.4 g (target: 0.1 g)
Hayabusa2 returned 54 times its required sample: 5.4 grams of asteroid material against a formal goal of just 0.1 gram.
It fired a copper impactor into Ryugu at roughly two kilometres per second to blast open an artificial crater, then landed beside it to collect pristine subsurface material, a first in planetary exploration.
Its MINERVA-II1 robots were the first rovers ever to operate on an asteroid's surface, moving by hopping because Ryugu's gravity is far too weak for wheels.
Laboratory analysis of the returned grains revealed amino acids and water-altered minerals, direct evidence that asteroids like Ryugu carried life's raw ingredients through the early Solar System.
The spacecraft itself never came home: after dropping its sample capsule over Australia it departed on an extended mission, targeting asteroid 2001 CC21 in 2026 and 1998 KY26 in 2031.
Hayabusa2 rewrote the playbook for sample-return exploration. Autonomous pinpoint touchdowns guided by dropped target markers, a kinetic impactor to expose buried material, hopping surface robots and a flawless capsule return showed that a modest-sized national mission could execute the most complex small-body campaign ever attempted. Its pristine carbonaceous samples, shared with laboratories worldwide and compared with NASA's later Bennu material, opened a new era of asteroid science bearing directly on how water and organic chemistry reached Earth. The mission cemented JAXA's leadership in small-body exploration, and its impactor experiment foreshadowed the planetary-defense techniques tested by missions like DART.