How Hayabusa2 got up close with an asteroidーNHK WORLD-JAPAN NEWS

[00:00:00]Japan's Hayabusa 2 space probe successfully carried out a historic mission earlier this month when it performed a flyby of an asteroid.

[00:00:09]>> And the mission aims to collect valuable data as well as insights into how to protect the Earth from potential asteroid strikes.

[00:00:19]>> Hayabusa 2 flew within close range of the asteroid 2001 on July 5th Japan time.

[00:00:25]This is a computer animation of the flyby. It represents the asteroid hurtling past the probe.

[00:00:33]Hayabusa 2 touched down on another asteroid Ryugu in 2019.

[00:00:38]It collected sand and dust samples and brought them back to Earth the following year. The probe then had its mission extended.

[00:00:48]During the flyby, Hayabusa 2 was supposed to get within a few hundred meters of the asteroid and capture images while traveling at a relative speed of 5 km per second.

[00:01:00]Pictures released the following day by the Japan Aerospace Exploration Agency or JAXA showed the mission had been a success.

[00:01:09]An image taken 1 second before Hayabusa 2 came closest to 2001 captures the rocky surface of the asteroid.

[00:01:18]A video created by connecting still images makes it look like the snowman-shaped asteroid is flying toward the probe.

[00:01:26]JAXA also observed the asteroid with other devices including a camera that can measure surface temperatures.

[00:01:33]The agency says it plans to analyze all the data from the probe.

[00:01:40]>> I didn't expect it would be able to take pictures like this. I'm so happy.

[00:01:46]>> We're joined now by our science correspondent Kōmoto Kyōta who's been covering the mission. So Kyōta, it looks like JAXA managed to obtain valuable data from the asteroid at 2001. But can you explain how this mission will contribute to protecting Earth in the future?

[00:02:01]>> Okay. Um there are more than 40,000 asteroids on orbits that come relatively close to Earth.

[00:02:07]And most of them are nothing to worry about.

[00:02:11]Um but there is non-zero possibility that some could make impact.

[00:02:16]In 2013, an asteroid entered the atmosphere and exploded over Russia.

[00:02:23]The resulting impact caused significant damage on the ground.

[00:02:28]Scientists are now looking for ways to keep the Earth safe, known as planetary defense.

[00:02:37]NASA has done experiments to change the orbits of an asteroid.

[00:02:41]And in fact, it succeeded.

[00:02:44]It managed to alter the path of an asteroid by deliberately crashing a spacecraft into it.

[00:02:53]This moment's flyby did not involve a direct a direct collision, but it required guiding a spacecraft on an extremely precise close proximity trajectory.

[00:03:06]If the technology to do this can be perfected, it could and eventually be used to strike an asteroid as well.

[00:03:17]And Japan is seeking to strengthen its capabilities in this field because planetary defense is an issue that concerns the entire world.

[00:03:28]>> Mhm. So, you've just said the flyby was really extremely precise. So, how challenging was it?

[00:03:34]>> Mhm. Flybys that come this close to an asteroid are said to be extremely rare.

[00:03:41]Mhm.

[00:03:41]This thing This animation represents the moment of the flyby.

[00:03:46]Hayabusa 2 passes near Torifune, shown in the center of the screen.

[00:03:52]At the closest point, they are only a few hundred meters apart.

[00:03:57]That's an extremely close pass.

[00:04:00]And remember, it was happening at high speed.

[00:04:04]The animation may make it look slow, but in reality, the spacecraft was traveling at a relative speed of 18,000 km/h.

[00:04:14]>> 18,000 km/h. So, it couldn't be couldn't couldn't it have slowed down?

[00:04:21]>> Mhm.

[00:04:22]If it slowed down, its trajectory would change.

[00:04:26]And the probe needs to stay on course for its final destination.

[00:04:32]So, it had no choice but to continue at its current speed and while taking photographs.

[00:04:41]The Hayabusa 2 operations team spent 6 years preparing for this flyby.

[00:04:47]Until the very last moment, they were conducting rehearsals to confirm all the procedures.

[00:04:55]Here's what the team leader had to say.

[00:05:00]>> We really just have one chance to get this right. Once it passes, that's it.

[00:05:05]It feels like everything is stacked on this one moment, so we're very focused.

[00:05:13]>> He also said that he believes Japan has shown the world what it can do in asteroid exploration.

[00:05:20]>> Mhm. And they likely inspired a bunch of young people to, you know, take an interest in space, too, right? Yes.

[00:05:26]Thank you very much for all your input, Kilta. NHK World's Kōmoto, Kilta.