Japan's Hayabusa2 spacecraft lands on asteroid Ryugu

The Hayabusa2 probe is designed to fire a bullet at Ryugu to retrieve rocks from the asteroid's surface.

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In a simulation, JAXA fired a tantalum bullet at a rocky surface to analyze how the debris would scatter.


Japan's Space Agency has been in a cosmic car chase with the spinning-top asteroid Ryugu since June 2018 -- and now, it's fired the first shot.

JAXA's Hayabusa2 spacecraft landed on the potentially-hazardous asteroid Ryugu just before 3 p.m. PT on Feb. 22 to a spattering of applause and high-fives.

"We did it! We made it!" said Seiichiro Watanabe on the livestream, project scientist with Hayabusa2, moments after touchdown. 

The Hayabusa 2 team celebrates after learning of the spacecraft's successful touchdown.


Hayabusa2 was designed to land on the rocky asteroid and collect a sample from its surface within just a matter of minutes. To do so, Hayabusa2 descends into position just above the surface and fires a tantalum bullet at the asteroid at around 650 miles per hour to kick up dust and debris. The team had previously simulated this process on Earth and crossed their fingers that all would go well 180 million miles away, too.

Watch this: Japan’s Hayabusa2 space probe fires bullet into asteroid

Hayabusa2's landing site on the asteroid was close to the equator, just east of Brabo crater, which gets its name from a Dutch story "Brabo and the giant." Ryugu itself was named after a dragon's palace in a popular Japanese folk tale and shares many names with fairy tales of old.


Brian May, ever the astronomer, appeared on the livestream before the mission to wish the team well.


Before the final touchdown, Brian May, rock legend, astronomer and Queen guitarist, appeared on the stream before Hayabusa was ready to touch down. May was also present when NASA's New Horizons zipped past the most distant world we've yet explored.

"Now I'm hugely happy to be, in a sense, part of the Hayabusa family because I've been able to process some images from Ryugu and this has been a thrill -- and it's a labor of love for me," the rockstar said. 

At 3:08 p.m. PT, JAXA confirmed that Hayabusa 2 had begun to rise from the surface of Ryugu.

"The results [are] exactly as we planned, there was some deviation from the simulation graph, but the results are such that everything went according to plan and that's impressive," Junichiro Kawaguchi, Hayabusa2 project manager, said shortly after the touchdown. 

The sample collection process only takes a matter of seconds and a "sample horn" collects the pieces of rock that flow out of the bullet wound. The maneuver was successful, according to JAXA's data, but what was collected?

"Of course, we don't know if the sample is collected," Kawaguchi continued, "we have to wait and see."

Unfortunately, there are no detectors or sensors on board to tell us exactly what Hayabusa2 picked up -- that will have to wait until the plucky little spacecraft returns to Earth.

Japan has form in this space though. It is currently the only nation to have retrieved samples from an asteroid when Hayabusa 1 nabbed samples in 2010. That spacecraft, launched in 2003, was also designed to fire bullets to kick up debris on the asteroid Itokawa. While it did retrieve samples from Itokawa's surface, the projectiles did not successfully fire. Speaking after today's landing, Kawaguchi described the Hayabusa2 mission as "revenge" for the failures of that mission.  

Notably, Hayabusa2 is fitted with more than one bullet -- it's actually a three-chambered space-gun! That gives Hayabusa2 another two chances to kick up more debris from Ryugu and potentially grab even more samples. Ryugu is expected to return to Earth in 2020.

NASA's own asteroid sample-retrieval mission, OSIRIS-REx, is currently in orbit around another potentially hazardous asteroid known as Bennu. It is expected to return to Earth with a sample from that asteroid in 2023 and NASA will share those results with its Japanese counterparts.