[ti:Japanese Spacecraft Heads Home]
[00:00.04]A Japanese spacecraft has left a distant asteroid
[00:05.38]and started its return trip to Earth after successfully completing its mission.
[00:14.52]The Japan Aerospace Exploration Agency, known as JAXA,
[00:20.80]said the Hayabusa2 spacecraft left its orbit around the asteroid Ryugu, Wednesday.
[00:31.44]The space rock is currently about 300 million kilometers from Earth.
[00:40.80]Hayabusa 2's mission was to gather soil samples and information
[00:47.24]that could provide clues to how the solar system formed, the country's space agency said.
[00:56.76]The spacecraft is to bring those samples back so scientists can study them in a laboratory.
[01:06.84]Workers at the command center stood up and cheered
[01:11.59]when JAXA project manager Yuichi Tsuda confirmed the departure.
[01:20.32]The spacecraft captured pictures of Ryugu as it began its return trip and sent them back to Earth.
[01:31.68]The asteroid Ryugu, or Dragon Palace,
[01:36.11]is named after a sea-bottom castle in a traditional Japanese story.
[01:44.28]Hayabusa2 will continue its "farewell filming" of the asteroid for a few more days, JAXA said.
[01:56.60]As the spacecraft travels away from the asteroid and toward Earth it will adjust its position.
[02:06.48]It will retreat about 65 kilometers from the asteroid and out of its the gravitational pull.
[02:16.92]After that, the asteroid will be out of sight of the spacecraft.
[02:24.24]"It's sad to say goodbye to Ryugu," Tsuda told reporters.
[02:30.48]"Literally it has been at the center of our lives over the past one and a half years."
[02:39.56]The spacecraft will then start its main thrusters in early December to power it back to Earth.
[02:51.00]The return trip will take about one year.
[02:56.60]"We expect Hayabusa2 will bring us new scientific insights," Tsuda said.
[03:04.69]"Not only the data, but tangible samples will be in our hands."
[03:12.72]Hayabusa2 arrived at the 900-meter-long asteroid in June 2018.
[03:21.88]The spacecraft touched down on the extremely rocky asteroid
[03:27.78]two times and successfully collected information and soil.
[03:35.40]The first touchdown took place in February.
[03:40.32]Hayabusa2 collected surface dust samples at the time.
[03:46.44]In July, it collected samples from beneath the surface of the asteroid
[03:52.53]after landing in a shallow hole that it had blasted.
[03:58.16]The operation was the first of its kind in the history of space exploration.
[04:06.92]Scientists said they detected small amounts of carbon
[04:12.28]and organic material in the asteroid soil samples.
[04:18.84]"They will allow us to explore how carbon, organic matter and water
[04:26.12]are scattered around in the solar system, why they exist on Ryugu,
[04:34.56]how they are related to the Earth," Tsuda said.
[04:40.32]JAXA scientists believe the sub-surface samples contain valuable data
[04:47.74]because they are unaffected by space radiation and other forces.
[04:54.96]They believe the samples could tell more about the beginnings of the solar system 4.6 billion years ago.
[05:06.92]Hayabusa2 is expected to reach Earth in late 2020
[05:12.34]and drop a container holding the valuable samples in the Australian desert.
[05:21.40]Tsuda said landing the container at the targeted spot will require precision controls.
[05:31.64]Details are still being negotiated with the Australian government, he said.
[05:39.52]After Hayabusa2 drops its container, the spacecraft may be used for another mission.
[05:48.92]The spacecraft took more than three years to arrive at the asteroid.
[05:55.88]But the trip home is much shorter thanks to the current positions of Ryugu and Earth in their orbits.
[06:06.60]Asteroids orbit the sun but are much smaller than planets or moons.
[06:13.76]They are believed to be among the oldest objects in the solar system
[06:19.65]and may help explain how Earth developed.
[06:25.08]They may even provide clues about the appearance of life.
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