On Friday, JAXA announced it had successfully completed a mission to collect material from the surface of the asteroid, the first of three planned attempts. It did so by firing a metal “bullet” from Hayabusa2 into Ryugu, kicking up a cloud of debris that could be collected by the probe.
“We have been quite persistent in making meticulous presentations,” project engineer Takanao Saiki told reporters in a news conference after the mission. “That persistence has resulted in this success today.”
In this latest stage of the mission, JAXA wanted to collect a sample from the asteroid’s gravelly surface that could be brought back to Earth and analyzed. But observations showed Ryugu was much rockier than expected, and scientists had to adjust their strategy for collecting the necessary samples.
Hayabusa2 is equipped with a tool that can propel “bullets” into the asteroid’s surface to kick up small fragments, which can be collected by a “sampler horn.” In December, scientists did a practice run back on Earth, shooting a simulation of the gravel on Ryugu to see how much material would be kicked up. The test revealed that the bullet would produce enough debris to collect for the mission.
In the days leading up to the mission, the Twitter feed for Hayabusa2 provided updates and invited space fans to watch it unfold via live stream. There were cheers in the control room when data came back to confirm a touchdown.
Ryugu has “a relatively high abundance of water and organic compounds,” said John Bridges of the University of Leicester, who has been studying materials brought back from the first Hayabusa mission, which collected samples from a different asteroid called Itokawa.
“It’s thought to be [made of] the really sort of primitive material from the start of the solar system,” he said, making it critical to scientists.
Scientists will get their hands on that primitive material in 2020, when the spacecraft is expected to return to Earth. Bridges said he was excited to study the findings.
“I’m sure it’ll throw up unexpected results,” he said. “But I’m pretty sure it will tell us more about the early solar system.”