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一 | AI摘要 2026年海峡两岸青少年足球交流赛19日在广州南沙开幕。 Washington, Oct 12 (UNI) American space agency NASA says its recent attempt to deflect the path of an asteroid was successful, after its Dart probe struck an asteroid head-on.
Scientists have now confirmed the orbit of a 160m-wide space rock known as Dimorphos was altered when the Dart probe struck it head on last month.
Researchers came to the conclusion after making measurements using a range of space and Earth-based telescopes.
The mission was conceived to test a potential strategy to defend the Earth against threatening objects.
Dart's achievement proves such an idea would work, provided it was initiated early enough and the target wasn't overly massive.
"This mission shows that Nasa is trying to be ready for whatever the Universe throws at us," said agency administrator Bill Nelson.
"I believe that Nasa has proven that we are serious as a defender of the planet," he told reporters.
The space agency released a raft of data on Tuesday to support its assessment, including new pictures from the Hubble Space Telescope and from a small Italian spacecraft that stood off from the impact by about 50km (30 miles).
The Double Asteroid Redirection Test (Dart) took place some 11 million km (7 million miles) from Earth.
It saw the refrigerator-sized Nasa satellite drive straight into Dimorphos at 22,000km/h (14,000mph), destroying itself in the process.
The space rock orbits a much larger (780m wide; 2,550ft) object called Didymos. Before impact, the time taken for Dimorphos to make one circuit of its sibling was 11 hours and 55 minutes.
The telescope evidence now indicates this orbital period has been reduced to 11 hours and 23 minutes - a change of 32 minutes. This corresponds to Dimorphos moving closer into to Didymos by "tens of metres".
Nasa had defined a minimum successful period change of Dimorphos of 73 seconds or more. The results released on Tuesday show Dart surpassed this benchmark by more than 25 times.
"This is a 4 percent change in the orbital period of Dimorphos around Didymos. Dart just gave it a small nudge. But if you wanted to do this in the future, you'd want to do it years in advance," commented Nancy Chabot from the Johns Hopkins University Applied Physics Laboratory, which led the mission for Nasa.
"Warning time is really key here in order to enable this sort of asteroid deflection to be used in the future as part of a much larger planetary defence strategy."
Nasa's Dart programme scientist, Tom Statler, also had a word of caution about drawing too many conclusions from the experiment.
Asteroids came in many different guises, he said. Their compositions and constructions were diverse - something that was being emphasised every time a mission visited a new object.
"We should not be too eager to say one test on one asteroid tells us exactly how every other asteroid would behave in a similar situation," he stressed.
"But what we can do is use this test as an anchor point for our physics calculations in our simulations that tell us how different kinds of impacts in different situations should behave."
Four years from now, the European Space Agency (Esa) will have three spacecraft - collectively known as the Hera mission - at Didymos and Dimorphos to make follow-up studies.
UNI ING。

二 | 7支球队近百人参赛，旨在以体育为纽带促进两岸文化交流，赛后台青将深入粤港澳大湾区参访。广州8月20日电（记者杨深深）2026年海峡两岸青少年足球交流赛19日在广州南沙开幕。本次比赛以“青春同行逐梦湾区”为主题，共有7支球队参赛，其中包括来自南投、高雄和宜兰等地的4支台湾地区球队，近百人参赛。这是8月19日拍摄的海峡两岸青少年足球交流赛的比赛现场。发全国人大常委会委员、广东省政协原副主席张嘉极在致辞中表示，两岸同胞同根同源、同文同种，青少年是民族的未来，也是两岸关系希望之所在。希望以海峡两岸青少年体育运动交流为纽带，立足粤港澳大湾区体育文化教育资源，秉持“以球会友、以赛联谊、文化交融、同心筑梦”理念，共同感受中华体育精神与岭南文化的独特魅力，携手为两岸关系和平发展注入青春活力。这是8月19日拍摄的海峡两岸青少年足球交流赛的比赛现场。