Japan’s Hayabusa2 capsule carrying asteroid samples recovered in South Australian outback

A capsule containing pristine asteroid fragments that may unlock secrets about the formation of the universe has been recovered in the South Australian outback after landing safely back to Earth on Sunday.

For the past six years, Japan’s Hayabusa2 spacecraft has conducted a remarkable 5.2bn km mission to extract the first-ever sub-surface samples from the asteroid Ryugu, which scientists hope will shed light on the origins of life.

In the early hours of Sunday, Hayabusa2 returned past Earth and dropped a capsule containing the precious sample, weighing less than 0.1 grams, down into the South Australian outback.

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The capsule briefly turned into a fireball and streaked across the sky as it returned to the Earth’s atmosphere, before landing in the Woomera prohibited area.

Search teams have found the capsule, about 40cm in diameter, and collection work had begun on Sunday morning.

As the capsule returned safely to Earth, staff with the Japan Aerospace Exploration Agency beamed and exchanged fist and elbow touches at the agency’s command centere in Sagamihara, near Tokyo.

“It was great ... It was a beautiful fireball, and I was so impressed,” said Hayabusa2 project manager Yuichi Tsuda from a command centre in Sagamihara, near Tokyo.

“I’ve waited for this day for six years.”

After it released the capsule, Hayabusa2 moved away from Earth to capture images of the capsule descending toward the planet as it set off on a new expedition to another distant asteroid. Its next mission will take a decade.

It is the second time a pristine, untouched asteroid sample has been brought back to Earth, but the first time an underground sample has been retrieved.

“Ryugu is extra special as it is thought to be the type of asteroid that carbonaceous meteorites come from,” Dr Eleanor Sansom, a planetary scientist and project manager of the Desert Fireball Network at Curtin University, said earlier this week. “If Hayabusa-2 samples match these carbonaceous meteorites, they could contain amino acids – the building blocks of life.”

In Canberra, Deep Space Communication Network director Ed Kruzins has been helping track Hayabusa2 since its launch in 2014. He said the mission was now in its most exciting phase.

“What’s particularly interesting about this vehicle is it runs solar-electric ion thrusters,” he said.

“So 66 kilograms of fuel can take you billions of kilometres. An extremely efficient way of manoeuvring.”

Professor Masaki Fujimoto, from Jaxa, said the asteroid samples may help answer a fundamental question: how did water and subsequently life, begin on Earth?

“Earth was formed close to the sun, so it was formed dry,” he said.

“Original Earth didn’t have water at all. So something had to bring water to our planet to make it habitable. Something like Ryugu brought water to earth and that’s why we are here.”

People who gathered to watch the capsule’s separation at public viewing events across Japan cheered the success. “I’m really glad that the capsule has been successfully released. My heart was beating fast when I was watching,” said Ichiro Ryoko, a 60-year-old computer engineer who watched at Tokyo Dome.

Australia’s science and technology minister Karen Andrews said the successful landing was an “incredible accomplishment” for Australia, which played a supporting role to Jaxa.

The agriculture minister, David Littleproud, said the sample would provide scientific evidence of any biosecurity risks from asteroids.

“After the sample is retrieved, JAXA will return the sample to Japan,” he said.

“The best minds on the planet will then analyse whether there are any space invaders, as far as biosecurity is concerned, on asteroids.”

Hayabusa2’s return comes weeks after Nasa’s Osiris-Rex spacecraft made a successful touch-and-go grab of surface samples from the asteroid Bennu. China, meanwhile, announced this week that its lunar lander collected underground samples and sealed them within the spacecraft for their return to Earth, as developing nations compete in their space missions.

The capsule, protected by a heat shield, briefly turned into a fireball as it reentered the atmosphere 120km (75 miles) above Earth. At about 10km (6 miles) above ground, a parachute opened to slow its fall and beacon signals were expected to be transmitted to indicate its location.

Jaxa staff set up satellite dishes at several locations in the target area to receive the signals. They also will use a marine radar, drones and helicopters to assist in the search and retrieval of the pan-shaped capsule.

A space rock expert from Australian National University, Trevor Ireland, who is in Woomera for the arrival of the capsule, said he expected the Ryugu samples to be similar to the meteorite that fell in Australia near Murchison in Victoria state more than 50 years ago.

“The Murchison meteorite opened a window on the origin of organics on Earth because these rocks were found to contain simple amino acids as well as abundant water,” Ireland said. “We will examine whether Ryugu is a potential source of organic matter and water on Earth when the solar system was forming, and whether these still remain intact on the asteroid.”

Scientists said they believe the samples, especially ones taken from under the asteroid’s surface, contain valuable data unaffected by space radiation and other environmental factors. They are particularly interested in analysing organic materials in the samples.

Jaxa hopes to find clues to how the materials are distributed in the solar system and are related to life on Earth. Makoto Yoshikawa, the mission manager, said 0.1 gram of the dust would be enough to carry out all planned research.

It is not the end of the mission Hayabusa2 started in 2014. It is now heading to a small asteroid called 1998KY26 on a journey slated to take 10 years one way, for possible research including finding ways to prevent meteorites from hitting Earth.

So far, its mission has been successful. Hayabusa2 touched down twice on Ryugu despite the asteroid’s extremely rocky surface and successfully collected data and samples during the one-and-a-half years it spent near Ryugu after it arrived there in June 2018.

During Hayabusa2’s first touchdown in February 2019, it collected surface dust samples. In a more challenging mission in July that year, it collected underground samples from the asteroid for the first time in space history after landing in a crater that it created earlier by blasting the asteroid’s surface.

Asteroids, which orbit the sun but are much smaller than planets, are among the oldest objects in the solar system and therefore may help explain how Earth evolved.

Ryugu in Japanese means “Dragon Palace,” the name of a sea-bottom castle in a Japanese folk tale.