SCIENCE & TECHNOLOGY

Left: The project would never have takenplace without international cooperation.
The capsule carrying the samples landed
in Australia, which had pledged anagreement to participate in the project.
© JAXA
Right: A container taken from the retrieved
capsule was weighed, confirming that it had
returned with a sample of 5.4 grams,
or 54 times the original goal of 0.1 grams.
Tsuda said jovially, “The analysis will be a
tough job because we collected so much.”© JAXA

Hayabusa2 navigated for three and a half years
through outer space before approaching theasteroid Ryugu, where it successfully toucheddown. (Image is computer-generated)©IKESHITA Akihiro

creating an artificial crater.
The mission’s success demonstrated that Japan
both possesses advanced asteroid exploration
technology and can be expected to contribute togreater understanding of the origin of the universe.
Analyses of the material from Ryugu, which scientists
believe contains evidence from the time of the solar
system’s formation some 4.6 billion years ago, could
yield hints about how our planetary system cameto be. In addition, as Ryugu is thought to containa copious amount of organic material and water,such analysis could validate the hypothesis thatthe organic material essential to life was carried to
Earth by similar asteroids crashing into our planet.
TSUDA Yuichi, project manager at the JAXA Space
Science Laboratory and the mission’s leader, said,“The Hayabusa2 mission sought to find the secrets
behind how the Earth and life were created.”
The probe’s predecessor, Hayabusa, completed thefirst-ever successful sample return mission in 2010by bringing material back to Earth from the asteroidItokawa. Despite facing several difficulties, including

ASTEROID EXPLORER

HAYABUSA2REVEALS THE ORIGIN
OF THE SOLAR SYSTEM
A Japanese probe succeeded in bringing to Earthasteroid samples that scientists hope will provide a key
to unlock the secrets behind the origin of life.

In December 2020, Hayabusa2, a probe launchedby the Japan Aerospace Exploration Agency ( JAXA),
after a journey of six years, brought back to Earthsamples collected from the asteroid Ryugu. The probe
was also the first ever to achieve the feat of extracting
a substance from below the surface of an asteroid by

The Hayabusa2 project involved 600 experts from Japan and elsewhere.
The team’s leader, TSUDA Yuichi of the JAXA Institute of Space andAstronautical Science, said that he respects the members’ meticulous work.
© JAXA

a fuel leak and engine failure, the probe miraculously
made it back home.
The frame and engine of Hayabusa2 were upgradedfrom the original model, while the JAXA teampersonnel conducted drills to deal with various
conceivable scenarios. These preparations werefully utilized during the eventual mission. With
touchdown being an incredibly high-risk operation,
the most difficult decision faced was whether tocollect a second sample from a different location.
A failed second landing would risk the loss of thesurface materials that had been collected on thefirst landing. “However,” Tsuda said, “in addition toproviding the opportunity to extract material frombelow the asteroid’s surface, the second touchdown
would be scientifically significant since obtaining
material from multiple locations would enable us to
conduct a comparative analysis. After reconfirming
the significance of an additional touchdown with
scientists from around the world, we chose to makethis difficult second attempt.” With the support ofscientists who believed in the technology carried by
Hayabusa2, the team was able to complete the second
landing successfully.
The enthusiasm and meticulousness of all the
project members bore fruit, enabling Hayabusa2 tobring samples back to Earth in a way that exceededexpectations. Looking back on the mission, Tsuda said,“Every single rock has its own unique surface. When I
saw the actual samples, I was moved to tears.”
Japan continues to be at the forefront of asteroidsample return missions. Hayabusa2, which has alreadymade a contribution to fundamental science, ispresently on its way to explore another asteroid in an
expanded mission. The probe is scheduled to arrive in
2031 and will surely lead to new discoveries.