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发布时间: 2025-05-24 18:04:04北京青年报社官方账号
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A Japanese space probe has successfully fired a "bullet" into an asteroid as part of a mission to collect rock samples from the celestial body.The projectile disturbed material from the exterior of asteroid Ryugu which then floated from its surface due to the weak gravitational field.These particles were successfully collected by the probe, according to Japan's space agency JAXA, which announced that the Hayabusa 2 craft had successfully touched down on on the asteroid on Friday morning Japanese time.JAXA scientists had expected to find a powdery surface on Ryugu, but tests showed that the asteroid is covered in larger gravel.As a result the team had to carry out a simulation to test whether the projectile would be capable of disturbing enough material to be collected by what scientists call a "sample horn," which protrudes from the underside of the probe.This video shows the success of a December 28 test, which green-lit the asteroid landing.The team is planning a total of three sampling events over the next few weeks.Hayabusa 2 will depart Ryugu in December 2019 and return to Earth by the end of 2020 with its precious cargo of samples, which will be analyzed by scientists such as John Bridges, a professor of planetary science at the University of Leicester, UK.Bridges, who was also involved in the first Hayabusa mission, told CNN via telephone on Thursday that the event was "nail-biting stuff" due to the extreme precision involved in landing on Ryugu."This is a significant mission," said Bridges. "Sample return missions are particularly exciting."He told CNN that the Hayabusa 2 mission is interesting because Ryugu is a C-class asteroid which humans haven't visited before."One thing I'm pretty sure of is that it will throw up some unexpected results," said Bridges, who believes that information from Ryugu samples could make us think again about the early evolution of the solar system.Beneath their desolate surface, asteroids are believed to contain a rich treasure trove of information about the formation of the solar system billions of years ago.C-type asteroids, which are largely composed of carbon, are the most common variety of asteroids, comprising more than 75% of those currently discovered. The other two main types of asteroid are the metallic S- and M-types, according to NASA.Ryugu is expected to be "rich in water and organic materials," allowing scientists to "clarify interactions between the building blocks of Earth and the evolution of its oceans and life, thereby developing solar system science," JAXA said.If Hayabusa 2 makes it back to Earth on schedule it will be the first mission to bring back samples from a C-class asteroid.JAXA scientists are currently racing NASA for that historic achievement, with the US agency's own sample retrieval mission due to arrive back on Earth in 2023.Even reaching the asteroid is a massive achievement as it is the equivalent of hitting a 6-centimeter (2.4-inch) target from 20,000 kilometers (12,400 miles) away."In other words, arriving at Ryugu is the same as aiming at a 6-centimeter target in Brazil from Japan," said JAXA.The-CNN-Wire? & ? 2019 Cable News Network, Inc., a Time Warner Company. All rights reserved. 3233

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145 business leaders have signed a letter demanding the US government take action on gun violence.Their plea, which follows the recent rash of mass shootings, is among of Corporate America's strongest statements yet against America's gun violence epidemic.In a draft letter addressed to the Senate, the leaders demand that lawmakers "support common-sense gun laws" already passed by the House and that "doing nothing about America's gun violence crisis is simply unacceptable." It was 496

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.@RFAMountsBay has been in the region since June in preparation for the hurricane season. She is equipped with specialist personnel, stores, and transport as well as a Wildcat helicopter #Dorianhttps://t.co/V1c9IgQY6G— Ministry of Defence ???? (@DefenceHQ) September 2, 2019 286

  

#targetdown I was able to get out in a little over an hour because my cashier would not give up. He had to scan every single item at least 10 times but it worked. They are still turning away people at the door. pic.twitter.com/jbEzBcIjmj— Naomi Thompson ?? (@NaominotNyomi) June 15, 2019 299

  

.@SenateMajLdr: “As a strong defender of the First Amendment, I believe Americans have the right to peacefully protest. However, today’s action toward Governor Beshear is unacceptable. There is no place for hate in Kentucky.”— Senator McConnell Press (@McConnellPress) May 25, 2020 294

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