Introduction
Although the record of successfully completed asteroid sample return missions is not
very extensive, the so-far completed pioneering missions will pave the path for future
generations of space scientists and engineers. By examining the history of these missions as well
as the technology that made them possible, scientists can deepen their knowledge of other
celestial bodies. Additionally, humanity may be able to discover how life originated on Earth and
how it may be present elsewhere in our Solar System.
History
The first spacecraft to return pristine samples from an asteroid back to Earth was the
Hayabusa spacecraft developed by the Japanese Aerospace Exploration Agency (JAXA).
Launched on May 9th, 2003, Hayabusa’s mission was to rendezvous with and collect samples
from the small near-Earth asteroid named 25143 Itokawa (Siddiqi, 2018). 857 days after its
launch, Hayabusa arrived at Itokawa, reaching a distance of 20 km from the asteroid (JAXA,
2010). Among Hayabusa’s instrumentation was also a MINERVA (Micro/Nano Experimental
Robot Vehicle for Asteroid) rover developed by the Institute of Space and Astronautical Science
(ISAS), which was deployed on November 12, 2005. Unfortunately, the deployment command
reached Hayabusa when it was at a higher altitude from Itokawa than intended, resulting in
MINERVA escaping Itokawa’s gravitational influence and drifting off into space (Siddiqi, 2018).
8 days after this deployment, Hayabusa executed a successful soft landing and collected a
material sample. 1666 days later, Hayabusa jettisoned the heat-shielded sample capsule just a
few hours before reentering Earth’s atmosphere. Although the main spacecraft burned up during
reentry (planned), the capsule landed in the Woomera Test Range in South Australia via
, parachutes. The next day, the capsule containing 1,500 grains of rock from Itokawa was
retrieved, completing the 7-year, 1 month, and 4-day long mission (Siddiqi, 2018).
On December 3, 2014, JAXA launched Hayabusa’s successor: Hayabusa2, whose
mission was to return samples from the near-Earth asteroid 162173 Ryugu. 1667 days after
launch, Hayabusa2 arrived at Ryugu, where it spent the next 504 days of its lifespan (departing
on November 13, 2019) surveying Ryugu, deploying rovers to its surface, and collecting samples
(JAXA, 2018). If the original Hayabusa’s MINERVA rover had successfully deployed on
Itokawa, it would have been the first mission where a spacecraft deployed an operational rover
onto an asteroid. However, Hayabusa2 accomplished this by successfully deploying several
rovers on the surface of Ryugu.
On February 21, 2019, Hayabusa2 collected its first sample from the asteroids surface
and 140 days later, collected another sample from underneath the asteroids surface. 389 days
after departure from Ryugu, the samples were successfully delivered back to Earth in a similar
manner to Hayabusa, concluding its initial mission (JAXA, 2018). However, instead of burning
up during atmospheric reentry, Hayabusa2 instead flew past Earth to visit new targets, using
leftover propellant, as part of a mission extension that will last at least through 2031.
In collaboration with NASA, JAXA is sharing a portion of their Ryugu samples in
exchange for a portion of samples from another near-Earth asteroid named 101955 Bennu,
collected by the most recent asteroid sample return mission to date: OSIRIS-REx (Origins,
Spectral Interpretation, Resource Identification, and Security-Regolith Explorer), which returned
samples from Bennu on September 24, 2023 (Donaldson, 2023). Before 2023, China plans to
join NASA and JAXA in successful asteroid sample return with the launch of mission Tianwen-2
(originally designated ZhengHe). The mission’s primary objective will be to collect 200-1000g
Although the record of successfully completed asteroid sample return missions is not
very extensive, the so-far completed pioneering missions will pave the path for future
generations of space scientists and engineers. By examining the history of these missions as well
as the technology that made them possible, scientists can deepen their knowledge of other
celestial bodies. Additionally, humanity may be able to discover how life originated on Earth and
how it may be present elsewhere in our Solar System.
History
The first spacecraft to return pristine samples from an asteroid back to Earth was the
Hayabusa spacecraft developed by the Japanese Aerospace Exploration Agency (JAXA).
Launched on May 9th, 2003, Hayabusa’s mission was to rendezvous with and collect samples
from the small near-Earth asteroid named 25143 Itokawa (Siddiqi, 2018). 857 days after its
launch, Hayabusa arrived at Itokawa, reaching a distance of 20 km from the asteroid (JAXA,
2010). Among Hayabusa’s instrumentation was also a MINERVA (Micro/Nano Experimental
Robot Vehicle for Asteroid) rover developed by the Institute of Space and Astronautical Science
(ISAS), which was deployed on November 12, 2005. Unfortunately, the deployment command
reached Hayabusa when it was at a higher altitude from Itokawa than intended, resulting in
MINERVA escaping Itokawa’s gravitational influence and drifting off into space (Siddiqi, 2018).
8 days after this deployment, Hayabusa executed a successful soft landing and collected a
material sample. 1666 days later, Hayabusa jettisoned the heat-shielded sample capsule just a
few hours before reentering Earth’s atmosphere. Although the main spacecraft burned up during
reentry (planned), the capsule landed in the Woomera Test Range in South Australia via
, parachutes. The next day, the capsule containing 1,500 grains of rock from Itokawa was
retrieved, completing the 7-year, 1 month, and 4-day long mission (Siddiqi, 2018).
On December 3, 2014, JAXA launched Hayabusa’s successor: Hayabusa2, whose
mission was to return samples from the near-Earth asteroid 162173 Ryugu. 1667 days after
launch, Hayabusa2 arrived at Ryugu, where it spent the next 504 days of its lifespan (departing
on November 13, 2019) surveying Ryugu, deploying rovers to its surface, and collecting samples
(JAXA, 2018). If the original Hayabusa’s MINERVA rover had successfully deployed on
Itokawa, it would have been the first mission where a spacecraft deployed an operational rover
onto an asteroid. However, Hayabusa2 accomplished this by successfully deploying several
rovers on the surface of Ryugu.
On February 21, 2019, Hayabusa2 collected its first sample from the asteroids surface
and 140 days later, collected another sample from underneath the asteroids surface. 389 days
after departure from Ryugu, the samples were successfully delivered back to Earth in a similar
manner to Hayabusa, concluding its initial mission (JAXA, 2018). However, instead of burning
up during atmospheric reentry, Hayabusa2 instead flew past Earth to visit new targets, using
leftover propellant, as part of a mission extension that will last at least through 2031.
In collaboration with NASA, JAXA is sharing a portion of their Ryugu samples in
exchange for a portion of samples from another near-Earth asteroid named 101955 Bennu,
collected by the most recent asteroid sample return mission to date: OSIRIS-REx (Origins,
Spectral Interpretation, Resource Identification, and Security-Regolith Explorer), which returned
samples from Bennu on September 24, 2023 (Donaldson, 2023). Before 2023, China plans to
join NASA and JAXA in successful asteroid sample return with the launch of mission Tianwen-2
(originally designated ZhengHe). The mission’s primary objective will be to collect 200-1000g
