Asteroid Sample Returns to Earth

In the early hours of Sunday morning, a bright fireball streaked across the skies above the red Earth planes of Coober Pedy in outback South Australia, heading for the Woomera Prohibited Area. To the cheers of many who witnessed the event in person by looking up and those around the world who watched updates, this marked the scheduled return of a special capsule, which has taken a journey across the Solar system over the last few years.

Contained within the capsule were samples from the asteroid Ryugu – a small rocky world which has been orbiting the Sun since before the Earth was formed over 4.5 billion years ago. The samples were collected by the Hayabusa-2 spacecraft, a mission that has been developed and operated by the Japanese Aerospace Exploration Agency (JAXA) since 2014.

Following on from its fiery re-entry into Earth’s atmosphere, the capsule deployed its parachutes and slowly floated back down to Earth, where recovery teams from JAXA, supported by Australia, awaited dawn before heading out to locate small containment unit.

Global space enthusiasts and planetary scientists are excited to uncover and analyse what’s contained within the capsule – pristine materials that are expected to revolutionise textbooks as the evolution of the Solar system is re-written, and potentially unlocking secrets as to how life formed here, in this random region of the Universe.

JAXA has been working closely with Australian authorities -and in particular, the Australian Space Agency – for the safe return and deportation (to Japan) of the Hayabusa-2 capsule. This included coordinating special licenses that allowed an object launched by a foreign country to be returned into Australian territory, as well as quarantining and transportation of the delicate cargo.

The Australian Department of Defence provided support and access to the prohibited zone in Woomera, and the Defence Science and Technology Group also assisted in conducting cooperative scientific activities with JAXA.

Minister for Industry, Science and Technology Karen Andrews congratulated JAXA on the landmark event, which she said strengthened Australia’s position as a desired partner for future international space missions.

“I extend a huge congratulations on behalf of Australia to the entire JAXA team on the successful landing and discovery of the Hayabusa2 sample return capsule,” Minister Andrews said.

“This is an incredible accomplishment for science and space and builds on our strong working relationship with JAXA, while also highlighting Australia as a nation with the trusted expertise to support international space missions.

Australian Space Agency Head Dr Megan Clark AC said the Agency was pleased to be able to support JAXA's successful return.

“Our team helped coordinate efforts across the Commonwealth and South Australian governments to plan for the Hayabusa2 re-entry - amidst pandemic restrictions - while also implementing our regulatory role to support the safe and successful return and recovery of the sample capsule in Woomera today,” Dr Clark said.

Recovery of the capsule was not the only part Australia played a vital role in – with a lot of the communication between Earth and the spacecraft coming from the NASA Canberra Deep Space Communication Complex, operated by our national science agency, the CSIRO.

“While this is a great achievement by the Japanese space agency, Australia can also be proud of the important role it has played in the mission’s success,” said Outreach and Administration Lead, Glen Nagle.

“To get to asteroid Ryugu and return home safely, Hayabusa2 was able to use the navigation, command, control and telemetry services provided by NASA’s Canberra Deep Space Communication Complex and the European Space Agency’s New Norcia station, both managed by CSIRO, Australia’s national science agency.”

“We have been working alongside our Japanese partners since the mission launched in 2014. We received the signals when Hayabusa2 made its historic touchdown on asteroid Ryugu in 2019. We are here today with our scientists, institutions and facilities as the samples are returned to Earth to reveal their secrets.” 

The Hayabusa-2 capsule also landed in an enormous region of Australia that comprises the traditional lands of six Aboriginal groups.

The asteroid Ryugu (officially 162173 Ryugu) is considered a potentially hazardous object, as it is a Near-Earth Object and part of a known collection of asteroids, called the ‘Apollo group’. The orbits of these asteroids cross the Earth’s orbit, and due to the size of some of the objects – this can present a risk in the distant future of it colliding with us.

Ryugu itself is about 1 km in diameter and shaped like two saucepan plates pressed against each other. Detailed images obtained from the Hayabusa-2 show a rocky world covered in boulders, dents, dusty surfaces, and a bulging equator.

Hayabusa-2 collected two different sample sets from two locations from the space rock – the first from the asteroid’s surface, and a secondary sub-surface sample obtained by firing a high-speed projectile into the asteroid.

This is the first time in history a sub-surface sample has been returned to Earth, thus presenting an exciting opportunity to analyse the pristine structure of minerals from the original Solar system formation, which have not been exposed to space weathering from other bodies.

The mission also left a few rovers on the asteroid – with four scientific payloads deployed to learn more about the asteroid’s gravity, surface features, and taking in-situ photographs.

Dr. Jonti Horner, who is the Vice-Chancellor Senior Research Fellow and a planetary scientist from the University of Southern Queensland also expressed his excitement about the mission.

"I'm really excited to see Hayabusa 2 return samples of Ryugu - it's an amazing achievement, and the second time the Japanese have managed to travel to nearby asteroids, gather samples, and bring them back home. I can't understate how incredible that is - they've brought home pristine pieces of an object that will help to reveal the fine details of the Solar system’s formation, 4.5 billion years ago. At the same time, they've helped to lay the groundwork for the extraction of resources from those objects (off-Earth mining), and even for our ability to deflect threatening objects that could otherwise collide with the Earth,” he said.

“When I was a kid, we’d only ever brought back samples from one celestial object – the Moon. In the past decade, the Japanese Hayabusa missions have tripled the number of places from which we’ve brought back samples. I’m fascinated to see what the samples will tell us about the Solar system’s past, and to see whether they offer any insights into how the Earth became the habitable world we know and love.”

With the successful landing and collection of the Hayabusa-2 capsule and materials from Ryugu, the first step in the analysis process is to conduct an atmospheric test within Australia. This test will analyse any gases that have been separated from the materials within the small sample that has arrived back on Earth.

From here, the remaining materials will be transported back to Japan to the Extra-terrestrial Sample Curation Centre, where an array of international scientists will commence further in-depth analysis.

As for the Hayabusa-2 spacecraft – it’s not finished yet. After deploying its package off at Earth, the re-ignited its engines, giving it a boost away from our planet, and onto its next targets – a flyby of another asteroid in 2026 and then a final rendezvous with a third asteroid in 2031.

This mission now also adds to the growing chorus of data and voices that support the migration of applications and services into space, in terms of both a regulatory framework and in-situ activities that will – in the not too distant future – mean that humans can work off-planet.

“Sample-return missions are now becoming a regular thing. Technology has allowed us to regularly land on objects and return back to Earth. With China’s Chang’e 5 landing on the Moon and returning in late December, Osiris-Rex, and future missions planned, we’ll be able to get our hands dirty and learn a lot about the Solar System and our own Earth.  What seemed like a distant dream years ago, our exploration in space is now becoming a reality," said Dr. Brad Tucker, a Research Fellow from the Australian National University and Outreach officer at Mt. Stromlo Observatory.

“The return of Hayabusa 2 to a landing site near Woomera represents another important milestone in Australia’s international engagement to promote and actively participate in the exploration and use of space for peaceful purposes. Our national legislative framework is designed to accommodate such missions, as had already been demonstrated by the successful return of Hayabusa 1 in 2010, and this latest mission is another in a long line of cooperative space activities involving Australia stemming all the way back to the 1950s,” said Professor Steven Freeland, a Professor of International Law at Western Sydney University and Director of International Space Law.

Video Credit: Hayabusa atmospheric return - JAXA