Six years and three days after launch, the Japanese Space Agency (JAXA) Hayabusa2 has completed its primary mission to study Asteroid Ryugu in detail, deploy four small rovers on its surface, and collect samples, including the first-ever subsurface sample from an asteroid. Now those samples are safely back on Earth.
This important payload landed in the Woomera desert in Australia between 5:47 and 5:57 pm UTC (12:47=57 EST). It is the same location where its predecessor Hayabusa dropped its asteroid sample. A team from JAXA has been in the southern country for the last month (partly due to Covid restrictions) to have all the preparations in place to collect the sealed container.
The surface and subsurface samples will be handled by the JAXA's Extraterrestrial Sample Curation Center. Once the sample is carefully released to make sure it is free from contamination, it will be possible for international scientists to request a fraction of it for their studies. The sample container is referred to as 玉手箱 (tamatebako), which translates to "treasure box".
Today, we celebrate the incredible technological advancement that allowed the collection of the samples. The surface samples were taken during a brief touchdown on the surface of Ryugu. To do so, Hayabusa2 shot a small projectile at the surface to lift the soil. Then, a sampling tube was used to suck up the debris. The collection of the subsurface sample similarly used a projectile, but it was a bigger and riskier job. Hayabusa2 shot a 2.5-kilogram (5.5-pound) bullet into the rock to expose sub-surface debris. The collection couldn't happen immediately because the debris could damage the spacecraft, so it had to wait for the literal dust to settle, then fly down to collect the material.
Even without the samples, the craft had already broken records and contributed to a better understanding of asteroids. The craft also successfully delivered the first-ever rovers to land on an asteroid, which sent back the first-ever images taken on the surface of an asteroid.
Today, marks an incredible achievement for JAXA and the Hayabusa2 team, but it is not the end. The spacecraft is embarking on an extended mission. Thanks to its extra propellant, the spacecraft will continue its explorations. It is now on an orbit towards a peculiar asteroid known as 1998 KY26, which Hayabusa2 will reach in 2031. This asteroid is just 30 meters (98 feet) in diameter, spinning around in just 10 minutes.
The next decade won't see Hayabusa2 idle. It will be studying the zodiac light, the dust in the plane of the Solar System that glistens in the sunlight, as well as observe exoplanets. It will also perform a flyby of the mid-sized asteroid 2001 CC21 in 2026, although the team is unsure if it will get much useful data as the mission was not designed for such quick observations.
The final objective is 1998 KY26, which is important in its similarity to other asteroids who are likely to impact Earth, so studying it up close will help us be better prepared against them.