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China steps up emergency response as Typhoon Dolphin approaches coast_我的网站

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【环球时报特约记者 陈山】在好莱坞科幻电影中,面对即将毁灭地球的小行星,发射航天器将其炸毁或撞飞的“套路”早已不再新鲜了。

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A 120-hour forecast track probability map for Typhoon Dolphin from 5 pm on August 7 to 5 pm on August 12. Photo: National Meteorological Center
    A 120-hour forecast track probability map for Typhoon Dolphin from 5 pm on August 7 to 5 pm on August 12. Photo: National Meteorological CenterMultiple national departments and local authorities have activated emergency response measures as Typhoon Dolphin, the 13th typhoon of 2026, approaches China's eastern coast, in an effort to safeguard people's lives and property.
China's National Meteorological Center (NMC) continued to issue a yellow alert for Typhoon Dolphin at 6 pm on Friday. As of 5 pm, the center of the typhoon was about 730 kilometers east of Wenzhou of East China's Zhejiang Province. It was packing maximum sustained winds of 48 meters per second (Level 15) near its center, with a minimum central pressure of 940 hectopascals. According to the NMC's tropical cyclone classification, Dolphin is classified as a severe typhoon.
Dolphin is expected to move westward at a speed of about 15 kilometers per hour while continuing to intensify. It is forecast to enter the East China Sea on Friday night and make landfall along the coast from Zhejiang Province to northern Fujian Province between Sunday afternoon and Monday morning. After landfall, it is expected to move west-northwestward and gradually weaken, according to the NMC's forecast.
At 6 pm on Friday night, China's Ministry of Water Resources launched a Level IV emergency flood response for Shanghai and the provinces of Jiangsu, Zhejiang, Anhui, Fujian and Jiangxi. The Ministry of Natural Resources activated a Level III marine disaster emergency response for Zhejiang, a level IV response for Shanghai, Jiangsu, and Fujian, and convened a meeting on Friday to coordinate marine and geological disaster prevention and response efforts for Typhoon Dolphin, making comprehensive arrangements for disaster preparedness, the Xinhua News Agency reported on Friday, citing the two ministries.
Coastal provinces have been stepping up preparations as Typhoon Dolphin approaches. According to Xinhua, authorities in Zhejiang Province upgraded emergency responses for Typhoon Dolphin from Level IV to Level III at noon on Friday. Fujian Province also upgraded its emergency response to Level III, according to provincial authorities. 
Typhoon Dolphin is expected to bring strong winds and heavy rainfall to parts of eastern China. According to Xinhua, from Friday to Tuesday, Zhejiang, Fujian, Jiangxi, Jiangsu, Shanghai and Anhui are forecast to receive heavy to torrential rain, raising the risk of flooding in major river basins and smaller rivers. Fujian authorities have also suspended some ferry and passenger transport services and closed tourist attractions in parts of the province as a precaution.
Xu Yinglong, chief forecaster at the NMC, said Typhoon Dolphin is currently being influenced by a combination of the subtropical high, the westerly trough-ridge system and multiple tropical systems, leaving some uncertainty over its track after landfall. Tropical disturbances over the Beibu Gulf and the western Pacific could also affect Dolphin's development and path, according to the official WeChat account of the China Meteorological Administration. 
As Dolphin approaches China's eastern coast, impacts from wind and rain are expected to intensify. Xu said the typhoon could bring stronger localized winds than Typhoon Bavi, the ninth typhoon of this year, while producing heavier and more widespread rainfall, with some areas likely to experience extreme precipitation.
From Friday to Saturday afternoon, waves of 7 to 13 meters are forecast in the East China Sea, while waves of 4 to 6.5 meters are expected in the coastal waters off Zhejiang. The coastal waters off Shanghai and northern Fujian are forecast to see waves of 3 to 4.5 meters. Meanwhile, storm surges of 50 to 120 centimeters are expected along the coast from the Yangtze River estuary to Fuzhou in Fujian Province from Friday afternoon to Saturday afternoon, the Global Times learned from the National Marine Environmental Forecasting Center.
Global Times 
。然而事实上,这种设想目前还停留在纸面上,从来没有得到过验证。美国“太空”网站9月13日称,人类“保卫地球”的行星防御计划到底能不能行得通,26日的撞击测试就将见分晓。一次关键的撞击 报道称,即将举行的测试属于美国国家航空航天局(NASA)的双小行星重定向测试(DART),旨在用一颗小型航天器撞击小行星,测试它对小行星轨迹的实际影响。

三 | 科学家们希望,如果未来有一颗危险的小行星威胁地球,类似DART这样的任务可以避免灾难的发生。NASA科学任务理事会副署长托马斯・祖布臣在12日举行的新闻发布会上说:“这些物体(小行星)在太空中飞驰,也在地球上影响了我们的历史。”“我们实施的一系列新任务正在帮助我们以前所未有的方式理解和量化这些威胁,DART是第一个尝试在实验中真正应对威胁对象的任务。” 2021年11月,搭载DART任务探测器的“猎鹰9号”火箭升空,开始长达10个月的太空旅行。DART选择了一颗名为Dimorphos的小行星,它的直径约160米,“像发条一样精准地”以11小时55分钟为周期围绕另一颗名为Didymos、直径800米的近地小行星运行。

四 | 这两颗小行星距离地球约1100万公里,不会对地球构成任何威胁。按照NASA的计算,自动售货机大小的探测器以每秒6公里的速度对小行星实施撞击后,后者的轨道周期将缩短约10分钟。为确保安全,这次撞击测试的地点远离地球,NASA精确测算了目标小行星的轨道特性,但对它的材质等更多信息了解得并不充分。因此探测器配备了自主导航系统,它将利用摄像头获得的图像自行选择撞击位置,并不间断地把整个过程传回地面指挥中心。为何需要实际测试 报道提到,尽管说起来简单,但撞击后的效果如何,还取决于很多因素。

五 | 首先是小行星的成分——它到底是由坚固的岩石还是松散的碎石堆组成?DART任务观测小组的负责人克里斯蒂娜·托马斯表示,如果是前者,那么撞击效果就如同在太空中玩台球游戏,“通过简单的物理方程就能推算结果”;但如果它是由数以千计的碎石组成,预测撞击的后果要困难得多。为了观测撞击的效果,NASA动用了詹姆斯·韦布空间望远镜和哈勃空间望远镜以及4个地面天文台轮流进行监测。托马斯表示,如果Dimorphos小行星是由碎石堆组成,这些望远镜应该能在撞击后数小时内捕捉到它的图像。此外,2024年欧洲航天局“赫拉”号航天器将造访这两颗小行星,进一步观察此次测试的影响。

六 | 约翰斯·霍普金斯大学应用物理实验室的DART项目协调负责人南希·查博特在新闻发布会上说:“我们想知道撞击Dimorphos会发生什么,但更重要的是,我们想了解这对未来可能的应用意味着什么。”报道称,与未来真正的小行星偏转任务相比,这次测试的规模非常小,但技术难度是一样的。据欧洲航天局测算,目前约有2.7万颗近地小行星,其中1200颗有撞击地球的可能性。NASA表示,直径超过1000米的大型小行星撞击地球,足以造成恐龙灭绝等级的严重破坏,但它们更容易被观察到,目前未发现可能撞击地球的此类小行星;而体积较小的小行星不足以对地球造成太大的破坏,大部分在穿越地球大气层时就被烧毁了。因此真正对地球构成威胁的小行星,直径通常在140米到1000米之间,它们更难被发现,但如果撞击地球仍可能造成大规模破坏。英国《金融时报》称,对于这类中等大小的小行星,DART将是人类最佳的应对方案。虽然在科幻电影中经常出现用核武器摧毁小行星的场面,但爆炸可能产生危险的太空岩石碎片,反而会成倍增加对地球的威胁。因此,需要用足够的力度撞击小行星使其转向,同时又不能太过猛烈,必须控制其产生的岩石碎片数量和方向,这需要借助DART任务为行星防御计划提供更多数据。中国也有“行星防御计划” 据介绍,DART所测试的只是行星防御计划的手段之一。

七 | 总体而言,行星防御是借助核爆、动能撞击、激光烧蚀、离子束牵引、引力拖曳、质量驱动等各种主动手段,破坏小行星的结构或者偏转小行星的轨道。

八 | 在今年4月24日的中国航天日当天,中国国家航天局副局长吴艳华首次向外界披露,我国将着手组建近地小行星防御系统,以应对近地小行星撞击的威胁,为保护地球和人类安全贡献中国力量。吴艳华表示,中国首先要完善建立地基天基对小行星的监测预警系统,不仅要编目,关键是分析判断哪些是重危型;要对是否有可能解除这些威胁进行技术研究和攻关。在完善对小行星探测能力的同时,中国也要着手组建近地小行星防御系统。吴艳华透露,未来中国将组织编制近地小行星防御发展规划,开发近地小天体防御仿真推演软件,并组织开展基本流程推演。他表示,要争取在“十四五”末期或者2025年、2026年实施一次对某一颗有威胁的小行星进行抵近观测,实施就近撞击,并就改变其轨道进行技术实验,为未来人类应对小行星等地外天体对地球家园的威胁,作出中国的新贡献。吴艳华还建议布局小天体防御关键技术研究,开展小天体防御任务关键技术验证,建立小天体防御任务地面模拟实验室,并适时启动实施我国主导的小天体主动安全防御任务。

九 | 此外,我国还应加强近地小行星防御基础研究。

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Published on:01:44:04