Journey to the Dragon Palace and Back

A Japanese spacecraft journeyed to an ancient rock and returned to Earth with a 4.6-billion-year-old relic of the early solar system. But it wasn't easy.

In a gray camouflage tee and blue denim jeans, Masaki Fujimoto is dressed all too casually for a man about to make history. Queen's Don't Stop Me Now has been playing on repeat, in his head, for weeks. One line is particularly prophetic for the 56-year-old astrophysicist.

"I'm burning through the sky…"

It's less than 48 hours from when a 16-inch-wide steel capsule will do just that, rocketing through the atmosphere before unfurling a parachute and gently landing in a sparsely populated area of the Australian outback. Locked inside is ancient cargo -- pieces of a 4.6 billion-year-old near-Earth asteroid collected by Hayabusa2, the star spacecraft in the Japan Aerospace Exploration Agency fleet.

Over the past six years, Hayabusa2 has achieved an extraordinary engineering triumph, filled with exhilarating firsts. It visited the dark, enigmatic Ryugu, an asteroid orbiting between Earth and Mars, and landed hopping robots on its surface. It imaged the exterior of the asteroid in exquisite detail and blasted a hole in its side with a copper cannonball. But the mission's masterstroke was sampling material from that wound it created in Ryugu's side, the first time a spacecraft has snatched rock from beneath an asteroid's surface. 


The spacecraft's achievements are some of the most valuable in the history of deep space exploration, akin to NASA's feats of landing rovers on Mars or exploring Pluto and its moons up close. On a smaller budget than NASA's, with a much smaller team, Japan wrote its way into space history. Yet for the mission to be considered a complete success, the team must land Hayabusa2's sample capsule safely back on solid ground.

Fujimoto, the deputy director general of JAXA's Institute of Space and Aeronautical Science, is responsible for bringing the spacecraft and its samples home. Trained as a theoretical physicist, he's leading the sample capsule recovery from the ground in Australia, overseeing nearly 80 scientists and engineers who have descended on the tumbledown outback town of Woomera. 

Flat, ochre plains stretch for miles. The closest town is two hours away. Few places are as desolate, and yet as accessible, as Woomera. 

The perfect place to drop an asteroid sample.

Hayabusa2's journey has been near flawless to date, but JAXA's runsheet never included "global pandemic." Travel restrictions forced Fujimoto to rewrite sample retrieval plans in April 2020, cutting the recovery team in half and mandating a quarantine period of 21 days for team members traveling to Woomera. 

"It's been a very intense eight months," he says.

On Dec. 4, 2020, just over a day before the sample's scheduled return, Fujimoto fronts a press conference in Woomera, discussing the mission. Over the past three weeks, he's hardly slept, but the only hint he's tired is a cappuccino he cradles in his hand. He takes a sip. "I don't think you can sleep in my position," he tells me.

Despite his scientific sensibilities, Fujimoto believes fate is guiding the asteroid sample back to Earth. Strange coincidences throughout the vehicle's six-year journey, he says, demonstrate this theory. Signs the mission is destined for success. 

The strangest of them all? On the night Hayabusa2's sample capsule comes careening back to Earth, the Woomera Theatre, which has 500 seats and only one screen, is scheduled to show Queen biopic Bohemian Rhapsody. 

Exterior of the Woomera Theatre and, nearby, a movie poster for Bohemian Rhapsody.

The Woomera Theatre was set to play the Rami Malek-led Queen biopic, Bohemian Rhapsody, just hours before the sample capsule's return.

Jackson Ryan/CNET

I. Keep Yourself Alive

Hayabusa2's journey began 18 years ago with its predecessor, Hayabusa. 

The original 2003 mission put JAXA on the world stage, highlighting its engineering prowess. The first asteroid sample-return mission ever attempted, Hayabusa was designed to travel to an irregular, slug-shaped body known as 4660 Nereus, briefly touch down on its surface, steal away pieces of rock and ferry them back to Earth. 

The thinking back then, Fujimoto says, was to perform a feat of cosmic exploration NASA "would never dare" attempt, but the mission was plagued by problems almost as soon as it launched. 

"Hayabusa was a very challenging mission," says Saiki Takanao, a mission engineer with JAXA. Its initial launch was delayed, forcing it to change targets to a bean-shaped asteroid named Itokawa. Then, during its cruise phase, it was hit by a massive solar flare -- during a year of hellacious sun activity -- disrupting its solar cells and decreasing the efficiency of its engines. It arrived at Itokawa three months behind schedule, and an attempted landing proved disastrous when a leak in the spacecraft's thrusters reduced its ability to manage its orientation. It spun out of control. Communication was lost. 


The team tried everything to locate the spacecraft. Junichiro Kawaguchi, the JAXA scientist who led the mission, even remembers visiting a small shrine, about five minutes walk from mission control, to ask for divine intervention. "Parents used to go to that shrine and pray their kid will come back," Fujimoto says. 

Within weeks, the spacecraft pinged home. 

Hayabusa cheated death, but two of its engines were busted. Data showed the spacecraft only glanced the surface of the asteroid and likely contained mere flecks of dust within the sample capsule. Clever engineering workarounds allowed the team to set course for Earth, but Hayabusa was headed for more misery. A third engine blew out on the way back.

It limped home three years late, ejected its sample capsule and slammed into the atmosphere. In its final moments, the spacecraft showered the skies over Woomera with thousands of fireballs. As the final sparks winked out, Hayabusa's mission came to a close. JAXA was not deterred by the original mission's problems, and plans for a sequel were already in motion. It would use Hayabusa as a starting point and visit an entirely new asteroid.

But if it was to succeed, the team would have to improve its futuristic propulsion system in just three years, half the time it had to build Hayabusa. 

II. Under Pressure

Ion engines appear to function as if by magic.

The complex wizardry that makes them work is officially known as "electric propulsion" and involves a mix of magnetic and electric fields, gas and plasma. But boil it down, and ion engines are essentially particle pinball machines strapped to the back of a spacecraft. Inside them, electrons collide with atoms to produce charged ions. These ions are pushed out of the engine at speed by a sustained electric field at the rear, delivering a very small amount of thrust. 

Unlike typical chemical engines, which use extreme amounts of fuel rapidly and deliver huge amounts of thrust in one big, violent burst, ion engines are designed to be used for tens of thousands of hours. They require a comparatively tiny amount of fuel. "If you need to do it fast, you use a chemical rocket," says Nathan Brown, an aerospace engineer at the Georgia Institute of Technology. "If you want to do it cheaply and efficiently, you use electric propulsion."

JAXA's only option with the Hayabusa missions was cheap and efficient. The agency operates on a budget roughly 5% of NASA's, with a team about one-tenth the size. The budget for Hayabusa2 is about one-third of NASA's for Osiris-Rex, an asteroid sample return mission the US agency launched in 2016

Though troubled, Hayabusa's ion engines, designed and built in house by now-ISAS director general Hitoshi Kuninaka and his team, provided a solid foundation for Hayabusa2. But the team was constantly under pressure. "We were behind schedule a lot of the time," says Ryudo Tsukizaki, a JAXA engineer.

Hayabusa2's engines would need to help carry the spacecraft 1.75 billion miles to reach its destination. Kazutaka Nishiyama, a JAXA engineer who led the ion engine team, says it was critical to increase the lifespan of the engines. Three of Hayabusa's engines failed at around 10,000 hours -- 14 months -- due to a critical component of the engine known as a "neutralizer." Tinkering with the neutralizer provided the necessary improvements to the lifespan. 

At the ISAS laboratory in Japan, an earthbound twin of the Hayabusa2's ion engine system is still being tested in a vacuum chamber today. When I talked to Nishiyama in October 2020, it had been switched on for 67,000 hours (seven and a half years). The early results of the test imbued the team with renewed conviction. 

Hayabusa2 launched on Dec. 3, 2014, from Tanegashima Space Center in Japan. By the time launch day rolled around, the stress and pressure of ion engine development had all but faded. "We were very confident," says JAXA engineer Tsukizaki. For large parts of the mission, it cruised through the dark, lit by the aqua glow of its ion thrusters and dim light from the sun. Unlike its predecessor, it had a faultless flight, marked only by an occasional wave of X-rays washing over the spacecraft and periodically stopping the engines. 

But when Hayabusa2 left Earth, it was headed to an asteroid without an official name. Its provisional designation, 1999 JU3, merely referred to the date and time of its discovery. The rock was a mystery.

"The asteroid is a new world," says Yuichi Tsuda, the project manager of Hayabusa2. "Before getting there, we do not know anything about it." 

In 2015, the team at JAXA put out a call to the Japanese public to name the rock. From 7,336 entries, the selection committee settled on one.



III. The Dragon Palace

According to an ancient Japanese folktale, some 1,500 years ago, the fisherman Urashima Taro pushed his boat out into the Sea of Japan, under a soft blue sky. Taro drifted on the waves for hours, waiting to hook a red bream or bonito. The other villagers thought of him as kindhearted but most believed him lazy and luckless. He often returned to shore empty-handed as the summer sun sank beneath the horizon.

But on this summer morning, Taro's fortunes reversed. His rod stirred, clattering against the boat. A catch! Excitedly, Taro drew the line, but as he reeled in the prize, he realized it wasn't a fish he had hooked. It was a turtle.

Taro delicately removed the line from the creature's mouth and returned it to the sea with a gentle prayer. He placed his hands behind his head and lay down, dozing off, the sun's heat prickling his skin. 


As he slept, a beautiful woman rose out of the sea. She moved as if carried by the wind, her long, black hair caught in a zephyr, crimson and blue robes trailing her in waves. Gliding toward the boat, she woke Taro with a soft touch, whispering to him.

"Don't be afraid," she said. "I am Princess Otohime. Today you showed me great kindness when you set me free from your hook. My father, the Dragon King of the Sea, sent me to you. He wishes for you to attend his palace beneath the waves. There, you may take me as your wife if you wish and we will live happily forever."

Urashima Taro agreed to go with the Princess to the Dragon Palace, Ryugu, an ornate castle made of coral and sand. There he met the Dragon King and married Otohime. In the enchanted land, he lived in an endless summer for three years.

By the fourth year, he grew restless. He'd fallen in love with Otohime, but began to worry about his elderly parents, alone at home. When he informed Otohime of his desire to return to them, she was crestfallen. She attempted to dissuade Taro from leaving but ultimately agreed to let him go, offering him a small treasure box, a tamatebako, tied with a silk string.

"If you wish to see me again, you must never open this," she told him. Taro nodded, agreeing he would never so much as loosen the string. At this, he was whisked from the castle under the sea back to his boat, bobbing in the Sea of Japan. The sun was descending. He glided back into shore.

As he disembarked and stood upon the beach, his heart filled with doubt. 


The village had changed. The Shinto temple he visited as a boy had been rebuilt with a new facade. The mountainside had been cleared of its trees. There were more houses than he remembered. The fisherfolk glanced skeptically at Taro as he bounced between houses, hoping to find his home. But he could not. Finally, an old man with a walking stick came by, and Taro asked where he might find the home of the Urashima family.

The old man laughed. "Do you not know the story of Urashima Taro?" he started. "The fisherman disappeared 400 years ago. Everybody says he drowned. His family is buried in the old graveyard."

Taro rushed to the graveyard. The tombstones of his family appeared decrepit and eaten by moss. A monument to his own death stood, crumbling, by their side. His parent's names were barely legible. At this, he believed himself to be the victim of some cruel illusion and returned to the beach, tamatebako in hand. 

In desperation, he tore the silk string off the box and opened it.

Immediately, he was engulfed by a white fog as cold as the ocean. He cried out, knowing he would never see the Princess Otohime or the Dragon Palace ever again. The ghastly mist soared out to sea. Taro, on the shore, watched it fade into the tender blue sky, disappearing against the clouds. 

Then, the burden of 400 years set upon his body all at once. His hair grayed, then fell out. His face drooped, his spine curled, his teeth dropped into the sand. 


IV. Now I'm Here

Asteroid Ryugu is nothing like its namesake.

Photos snapped by Hayabusa2 as it approached the rock showed a featureless gray diamond against the dark; a milky splotch on a black curtain. But when the spacecraft arrived on June 27, 2018, and moved within 12 miles of Ryugu's surface, its cameras captured every dip, bend and curve of its face. The team was shocked. 

A view of Ryugu from great distance, taken by the Hayabusa2 spacecraft.

An image of Ryugu, taken by Hayabusa2's ONC-W1 camera on June 13, 2018, as the spacecraft began its approach.


It was no palace. It was a wasteland. Strewn with mammoth boulders and pockmarked by craters, Ryugu was immediately deemed "unfriendly" by members of the science team. "It was beyond our imagination," says Tsuda, project manager on the mission. "It's a really hopeless terrain."

Ryugu is what's known as a "rubble pile," a clotted mass of rock bound together by gravity. It likely formed when two large bodies collided in the earliest epoch of the solar system, some 4.5 billion years ago. The explosive impact would have showered space with debris. Over time, gravity pulled the wreckage together, forming Ryugu. It's been wandering in the orbit between Mars and Earth ever since. 

Asteroids aren't considered sexy. They're dull, bumpy boulders traveling through an abyss. They're oft-maligned; we only really care about them when we think they might collide with the Earth. This is unfair. Asteroids are some of the most valuable resources in our solar system.

"Missions like Hayabusa and Hayabusa2, and Osiris-Rex, are a first step towards deflecting asteroids, and also mining them," says Jonti Horner, an astrophysicist at the University of Southern Queensland. Asteroid mining is too expensive to be feasible today, but demonstrating that samples can be gathered and returned from distant space rocks could lead to a greener, near-unlimited resource of Earth metals like copper, nickel and platinum. A similar process, Horner says, might help change the trajectory of an asteroid on a collision course with the Earth. 

"One of the ways we could deflect it would be to send spacecraft there, land on the surface, and start digging bits off and firing those bits into space -- in a carefully calculated direction," he says.

The asteroid Ryugu as seen from the approaching Hayabusa2 spacecraft.

Ryugu, the Dragon Palace, captured by Hayabusa2's ONC-W1 camera on June 30, 2018. 


But asteroids aren't just destinations to visit, mine or move. They are also records of truly ancient history. 

Rocks like Ryugu could hold clues to the evolution of the solar system and even the evolution of life on Earth. Observing Ryugu for over a decade, scientists learned it was a "C-type" asteroid rich in carbon, containing some of the oldest and most pristine material we know of, from a time when planets were only just beginning to form. They are believed to harbor water ice and organic compounds, making them "potentially important for supplying the basic ingredients for life on Earth and other planets," says Simon Turner, a geochemist at Macquarie University in Australia.

JAXA would be the first agency to visit a C-type asteroid and sample rock from its surface. But the team quickly realized just how problematic that surface would be.

V. Spread Your Wings

If you want to tango with an asteroid, you have to have a really big dance floor. 

"We needed a 100-meter-diameter flat area," says Tsuda, "but there's no such space on the surface of Ryugu." He was acutely aware of how things could go wrong, having worked on the first Hayabusa mission.

Hayabusa2 performed a touchdown rehearsal in September 2018, a month before the first landing operation was scheduled to occur. It approached Ryugu slowly, scanning the surface with a laser that gauges altitude. At a height of 600 meters, it stopped descending. The spacecraft had a memory lapse, losing track of the distance to the surface. To save itself, it autonomously backed away. After reviewing the issue, the team decided on postponing the first touchdown. They needed to find a good landing spot. 

Scientists scoured images of Ryugu's surface, measuring the size of shadows cast by boulders and pebbles to estimate height. Tsuda thinks the science team counted 10,000 or more rocks to estimate the "bumpiness" of the terrain. After a week, the team located a safe area, dubbed L08-B, that was free from debris -- but it was one-fifth the size they required.

Tsuda reasoned that the team would have to rethink its strategy altogether. They would now perform a "pinpoint touchdown" method and, Takanao says, had to "study very, very hard" to pull it off.  


JAXA members Hirotaka Sawada (left) and Satoru Nakazawa (right) in the Sagamihara control room during touchdown rehearsal on Sept. 11, 2018.


Originally, Hayabusa2 planned to drop a softball-sized, reflective marker to the surface during the touchdown operation and then follow it to the surface. But the team reasoned that if it dropped the marker a few months prior to touchdown, that would provide Hayabusa2 with a beacon it could use as a guide, like a lighthouse shepherding a ship to shore. 

Fortunately, Hayabusa2 had already proved itself a sharpshooter. It had deployed two hopping rovers, Hibou and Owl, to Ryugu's surface, along with a third robotic scout, Mascot, developed by the German Aerospace Center and France's National Centre for Space Studies. The box-shaped hoppers were the first spacecraft to image an asteroid from the surface and measure properties never considered before. When it came time to land the target marker, the operation proceeded without fault.

Although the successes were mounting, the reason for visiting Ryugu was to sample it. "Without a successful touchdown, we could not go beyond Hayabusa," says Tsuda. Touchdown was all he could think about. He wasn't getting much sleep, he says. In late October 2018, the team dropped the target marker without issue. Two more touchdown rehearsals occurred in the new year, and the pinpoint method worked flawlessly. Finally, the team was ready.

With the sun rising over mission control in Sagamihara on Feb. 21, 2019, Tsuda donned his off-white Hayabusa2 mission jacket, and the team began its operation. The control room was calm. Expectant. But as they performed final checks on Hayabusa2 before descent, the mission was thrown into chaos.

Hayabusa2 was not where it was supposed to be.


VI. Get Down, Make Love

The distance between Earth and Hayabusa2, floating above Ryugu, is about 210 million miles. Orders, uploaded from Japan, take about 20 minutes to reach the spacecraft. It's programmed to perform operations autonomously and, if something goes wrong, there's no opportunity to correct on the fly. 

When JAXA found Hayabusa2 was not in position to start its descent, the touchdown plan had to be reworked once again. "We had to delay the start of the descent by five hours," says Tsuda. The slight delay might not seem significant, but in that time the team essentially reprogrammed Hayabusa2's guidance systems for the operation. 

The "last hardship," as Tsuda calls it, changed the atmosphere in the room, but only slightly. The team quickly discovered a timing error had caused the mishap. They'd trained hard for these exact scenarios, running simulations hundreds of times on the ground. Tsuda's confidence and anxiety coalesced in the frenzied five-hour pause.

Finally, just after midday on Feb. 21, the touchdown operation was declared a "go." The new commands had been uploaded. The fate of Hayabusa2 rested solely in the spacecraft's hands. It descended. 

Dozens of members crowded around a wall-size projection, in the control room, providing a readout of data streaming back from Hayabusa2. There was no live video, so the team followed the spacecraft's Doppler data: Against a gray table, drawn like a graph in Excel, they waited for a red line to appear -- a sign the spacecraft had survived its encounter with Ryugu and was moving away from the surface.


Takanao Saiki (front) and Yuichi Tsuda embrace.


The pressure was huge, Takanao, the engineer, says. As the team waited, Sakanao interlaced his fingers, as if in prayer, staring at the screen. Almost 25 hours after JAXA began the operation, the thin, red line blinked into existence on the screen. They'd done it. Hayabusa2 was not equipped with cameras inside the sample capsule, but data streaming back from the spacecraft showed it had fired its projectile and picked up a bucketful of material, storing it away for the return journey. 

Applause broke out. Tsuda and Takanao high-fived. Team members embraced. The muted celebrations might have seemed strange to those used to watching broadcasts from NASA control rooms; energetic displays of relief and joy overwhelming team members. That wasn't the JAXA way. Tsuda recalled the feeling as one of "pure pleasure" and surprise. "We actually did that?" he asked himself, as other scientists wrapped him in fleeting hugs.

Hayabusa2 had done what Hayabusa could not. It had retrieved innumerable treasures from the ancient space rock. The team nicknamed the touchdown site Tamatebako.

With its treasure box tucked safely away, the spacecraft could have waited the year out, analyzing Ryugu from orbit until it was time to return home. JAXA wanted to go one better. 

VII. Stone Cold Crazy

One of Hayabusa2's major upgrades was the addition of a bomb.

Strapped to the underside of the spacecraft was an explosive known as the Small Carry-on Impactor that JAXA scientists, including Takanao, had designed for Hayabusa2 to drop on Ryugu to create an artificial crater and allow the team to sample material from beneath the asteroid's surface. But the team agonized over one key decision: Should they use it?

A second touchdown was a risky operation. Would JAXA take a chance on losing the ancient cargo it had already captured to perform another risky touchdown and nab this pristine material? There was great uncertainty within the team.

Fujimoto says there were many "interesting" conversations leading up to the operation, describing heated debates about whether it was worth the risk. Tsuda notes that the first touchdown was "mandatory" for the mission's success, but the second touchdown was "the first time we purely pursued the scientific value."

It wasn't necessary to extract the first subsurface sample from an asteroid, but the team's scientists wanted to try. The material could unravel some of the secrets of C-type asteroids. For Fujimoto, not trying to collect the subsurface sample was akin to revealing the team wasn't confident in itself. He didn't want to risk "getting that reputation," he says. Eventually, a consensus was reached: They would go for it.

On April 5, 2019, a 4.4-pound copper disc was volleyed from the SCI at a speed of 2 kilometers per second. It collided with Ryugu's side and sprayed rock across its body, leaving a scar on the surface about 32 feet wide and six feet deep. "This exposed subsurface material around the artificial crater," Tsuda says. 

The SCI departing Hayabusa2 en route to bombing Ryugu. 


Scientists could pick practically anywhere safe on the surface for Hayabusa2's first landing. But for the second, there were no options. "To collect subsurface materials, we must land near the artificial crater," says Shota Kikuchi, a JAXA engineer who helped plot the second landing. But the team did get "really lucky," according to Yuri Shimaki, a post-doctoral engineer at ISAS, because the SCI hit at such an angle that Hayabusa2 could retrieve an abundance of ejected material. Not before a lot more training, though.

The engineering and science teams simulated touchdown operations from the mission control room on Earth, running through hundreds of scenarios. One team member would be assigned the role of "God," tasked with simulating the entire second touchdown from start to finish. 

During one simulation, "God" was in on a conspiracy to derail the simulation. The member had tasked one of the engineers to complain of stomach problems, right as the spacecraft in the sim began its descent to the surface. The engineer played along, crying out in pain, rushing to the toilet and disappearing. But the simulated mission carried on in that engineer's absence. 


"Make the most of your chances!" The Ryugu-no-tsukai in JAXA mission control.


Tsuda says the team pulled together and, ultimately, the simulation was a success. 

On July 10, 2019, the second touchdown operation began. It was a carbon copy of the first, but this time a plush Japanese oarfish (a "Ryugu-no-tsukai") hung in the room with a message: "Make the most of your chances! That is the principle of space research!"

Team members huddled around the Doppler data on the wall for a second time. At 10:51 a.m. on July 11, Tsuda declared the mission a success. The celebrations, too, were a carbon copy, but this one meant a little more. JAXA had taken the risk and succeeded. Looking back, Fujimoto calls the second touchdown "one of the defining moments" of his career. 

With two bags of ancient rock now stowed safely within its sample capsule, it was time for JAXA to bring Hayabusa2 home. 


VIII. We Will Rock You

In Japan, JAXA hasn't always been seen as a space powerhouse. A difficult decade of launch failures and satellite deaths marred the Japanese space program before Hayabusa's launch in 2003. As troubled as that mission was, Hayabusa overcame nearly insurmountable odds and provided a launchpad for the agency's profile to skyrocket. 

"When people in Japan find out I work at JAXA, they say it's very cool and awesome, no matter the age group or profession," says James O'Donoghue, a former NASA planetary scientist now working at ISAS. He says the interest in JAXA seems similar to the American interest in NASA during the 1960s and 1970s. 

But internationally, JAXA doesn't receive the same level of adoration as its counterparts at NASA or the European Space Agency. Partly that's due to the language barrier. Elizabeth Tasker, an astrophysicist with JAXA who led the English efforts for Hayabusa2, is responsible for delivering mission updates and releases from the agency. She says "there's no reason in terms of the science they're doing not to get equal levels of recognition."

NASA has outreach down to an art, but JAXA is still learning how to promote itself. Fujimoto says this is partly born out of cultural beliefs in Japan. "You don't identify yourself as the heroes," he says. "It's something to be said by somebody else."

In the three months I spent interviewing team members prior to sample return, the emphasis on JAXA's teamwork really shone through. Members like Tsuda, the project manager, had become familiar faces around the world, while Fujimoto had overseen success after success, and yet they remained reluctant to praise themselves or their abilities.

"I just played my role," Fujimoto says. 

But as Hayabusa2's achievements mounted, there was plenty to celebrate. JAXA resolved to tell the spacecraft's story to the world and its outreach efforts dramatically increased. It even enlisted the help of Queen guitarist Brian May, himself an astrophysicist, to produce stereoscopic images of Ryugu's surface. The work enabled Ryugu to be seen in a new light, which, May says, "makes us feel like we are sitting next to these incredible objects." He's been thoroughly impressed by the JAXA team.

"All round, it's been an amazing spectacle and I think a great example of how efficiently a solar system mission can be executed," he says.

Outreach is particularly important when it comes to diversity, too. In the celebratory images from mission control in Sagamihara, few women are present. "It's a bit surprising, isn't it?" says Moe Matsuoka, a post-doctoral researcher at ISAS who worked on infrared imaging of Ryugu. She is hopeful her work and the success of Hayabusa2 can begin to inspire the next generation of Japanese women into STEM fields.


IX. Don't Stop Me Now

On the day before landing, I corner Fujimoto after his press conference in Woomera and we discuss the mission so far. We've been talking online for weeks, and now, meeting for the first time, I want to shake his hand and say hello. But I can't. A face mask is draped over my ears, the mission name and date embroidered with blue thread on the front. 

This is what it means to return an ancient asteroid sample during a pandemic. 

When Hayabusa2 departed Ryugu on Nov. 13, 2019, it was the Before Times. A huge contingent of JAXA staff were preparing for a trip Down Under to witness the end of their decade of hard work. COVID-19 saw those plans disintegrate. 

Just to get to Woomera, Fujimoto and the team of 79 scientists and engineers spent three weeks quarantined in hotels across Japan and Australia. They performed mission-critical training via Microsoft Teams and went through daily checklists speaking down the barrel of laptop webcams. When they eventually reached Woomera, they had to deal with masks and social distancing in the Outback's sweltering heat. 


On the drive to Coober Pedy, a storm began to brew over the flat, empty plains. 

Jackson Ryan/CNET

It was so hot that members of the crew felt woozy as they established radar stations to track the capsule's return in the Woomera Prohibited Area, a former nuclear test site about half the size of the United Kingdom.

The plan is for JAXA members to scour the WPA for the capsule shortly after it touches down on Dec. 6, but everyone else is instructed to leave Woomera and travel to Coober Pedy, an underground opal mining town about three and a half hours drive northwest. The skies over Coober Pedy will provide the best view of the return -- the moment the capsule slams into the atmosphere and transforms into a blazing fireball. 

As I drive out toward the underground locale, one final hurdle materializes on the horizon. Menacing clouds stretch across the sky, threatening to burst. With a crack, they spill. The rain is torrential. Back in Woomera, Fujimoto and members of the Australian Space Agency are anxious. He tells me they began checking the weather forecast religiously, bouncing between different reports, hoping to find a prediction that suits.

Clear skies aren't necessary for the sample to return to Earth, but rain and clouds will hamper the capsule's recovery mission. Still, Fujimoto holds on to his positive emotions -- the "Don't Stop Me Now" mentality he's carried the whole operation. When he heads toward the operations room deep within the Prohibited Area at midday on Dec. 5, he sees the skies clearing to the west. 

"We're gonna make it," he thinks to himself.

X. We Are the Champions

At 3:20 a.m. on Dec. 6, my phone's alarm begins to chime. Queen's Crazy Little Thing Called Love punctuates the silence. I was feeling superstitious when I set it the night before.

The blue light illuminates the darkness of the underground-cave-dressed-as-a-hotel-room I've booked for the night in Coober Pedy. Almost directly above my room is a lookout, a gravelly hillside, that a brochure tells me provides "the best view of town." That makes it a perfect spot to watch Hayabusa2's sample capsule return.

Video of the fireball taken from Coober Pedy on the morning of Dec. 6, 2020. 


I climb up the steel steps to the top of the lookout, where I'm met by a chilly breeze and a dozen other stargazers. Fortunately, the storm clouds from earlier in the day have all but disappeared. My eyes adjust to the night sky, and stars blink into sight. A dozen visitors mingle about, trading hometowns and occupations in lieu of longer narratives -- there's no time for in-depth conversation because, in just a few moments, Hayabusa2's treasure boxwill cut through the dark. 

Two American couples have set up recording equipment, ready to capture the capsule's return in high definition. We have a brief exchange about where the capsule will first appear. I politely let them know their cameras are pointed the wrong way. 

Just before 4 a.m., a streak of light materializes in the sky. The capsule. The Americans now realize their error, amid the "oohs" and "wows" of the gathered crowd, and pivot their recorders 180 degrees. Others point their smartphone cameras at the sky. A few claps erupt. From our vantage point on top of the lookout, the capsule moves slowly and deliberately, an unwavering line of light headed toward the horizon. But that doesn't reflect the violence taking place overhead.

The sample capsule slams into Earth's atmosphere travelling at 12 kilometers per second, covering a distance of almost 246 football fields in the blink of an eye. The air in front of the capsule is compressed so dramatically that the outer carbon fiber heat shield reaches temperatures of up to 5,000 degrees Fahrenheit, causing the capsule to glow about as brightly as a crescent moon. 

As quickly as it came, it disappears. 


Satoru Nakazawa, who led the recovery operation in Woomera, and the Hayabusa2 jackets worn by JAXA team members. 

Jackson Ryan/CNET

Two hundred miles to the southeast, the capsule is slowing down, just as expected. As it reaches an altitude of about 10 kilometers, it deploys a radar-reflective parachute and ejects its heat shield. Ground stations established across the desert track its descent. Half an hour later, JAXA mission control in Woomera calls touchdown. After 2,000 days in space, Hayabusa2's tamatebako is finally safe on Earth. 

A masterly, ordered recovery process marks the beginning of the end for the operation. It's a bittersweet moment for all JAXA team members. Relief, mixed with melancholy. Once all the ground stations are packed up and the sample capsule has flown back to Japan, most of the scientists and engineers will move on to new projects. "We achieved one thing, but we're going to lose another thing," Fujimoto says. "The team."

XI. The Show Must Go On

In the following days, the sample capsule is transported to Japan and delivered to the ISAS campus at Sagamihara. Team members line the street to watch the capsule arrive, as if it's royalty returning from a distant realm, cantering toward a castle. 

In some ways, it is. The sealed capsule contains relics from a distant kingdom, the Dragon Palace, that could answer some of the fundamental questions about life on Earth. Fujimoto jokes with me that when they open up the capsule and look inside for the first time, he hopes they play We Are The Champions. "That would never happen," he laughs. 

Ten days after retrieval, scientists at JAXA lift the lid on the tamatebako for the first time. Thankfully, they don't age rapidly in seconds, but what they find inside is almost as surprising as the curse of Urashima Taro. 


Yuichi Tsuda (left), project manager on the Hayabusa2 mission, and Masaki Fujimoto, deputy director general of ISAS.


Hirotaka Sawada, one of the members of the capsule recovery team, is the first person to lay eyes on subsurface material from an asteroid. He's looking through a window into the past, at rocks gathered 200 million miles from home. Clues, perhaps, about where we came from. The moment leaves him speechless. "That is the most happy time of my life," he says. 

Within the tube, he finds dozens of pebbles, up to a few millimeters in length, packed tightly into the metal tube. Sawada says some were even larger than the team expected. In 2021, the samples will be divided up and analyzed extensively. JAXA plans to share some of them with NASA scientists and hopes to compare them with the US agency's own asteroid samples, which the spacecraft Osiris-Rex retrieved from asteroid Bennu in October 2020.

For the Hayabusa2 mothership, the mission carries on for another decade, heading to ever more mysterious, unexplored worlds. The spacecraft will perform multiple flybys of the Earth over the next decade, tinkering with its trajectory enough to visit two asteroids by 2032. The show must go on.

But as this act came to a close, I had to know. Had the record player in Fujimoto's head finally changed tracks? Would he finally be singing We Are the Champions? 

"You know, Hayabusa2 is not the end," he says. "We have the next mission. So it's not really that We Are the Champions," he says.

"It's still Don't Stop Me Now."


Credits: Artwork by Realizm. ONC-W1 images: JAXA, Tokyo University, Kochi University, Rikkyo University, Nagoya University, Chiba Institute of Technology, Meiji University, University of Aizu, AIST. The tale of Urashima Taro: adapted from Lafcadio Hearn's "The Dream of a Summer Day."

This piece was originally published with the title "Journey to the Dragon Palace: Inside Hayabusa2's history-making asteroid mission" on March 17, 2021. It has been republished on June 30 to coincide with Asteroid Day