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原標題：韩国电影2017r级

學習快評丨qibao666888　　北??(bei)京??(jing)天??(tian)文??(wen)館?(guan)的??(de)科??(ke)普??(pu)專??(zhuan)家??(jia)介??(jie)紹??(shao)??，土??(tu)星??(xing)環(huán)??(huan)完??(wan)全??(quan)側(cè)??(ce)對??(dui)地??(di)球??(qiu)時??(shi)??，是?(shi)天??(tian)文?(wen)學??(xue)家??(jia)獲??(huo)得??(de)研??(yan)究?(jiu)環(huán)??(huan)系??(xi)三??(san)維??(wei)結(jié)??(jie)構(gòu)??(gou)的??(de)絕??(jue)佳??(jia)機??(ji)會??(hui)??。??微??(wei)弱??(ruo)的??(de)光??(guang)影??(ying)變??(bian)化??(hua)可??(ke)能??(neng)揭??(jie)示??(shi)土??(tu)星?(xing)環(huán)??(huan)塵??(chen)埃??(ai)分??(fen)布??(bu)的?(de)異??(yi)常??(chang)??，這?(zhe)種??(zhong)特??(te)殊??(shu)視??(shi)角??(jiao)帶??(dai)來??(lai)的??(de)觀??(guan)測??(ce)窗??(chuang)口??(kou)??，就??(jiu)像??(xiang)為??(wei)宇??(yu)宙??(zhou)CT掃??(sao)描??(miao)打??(da)開??(kai)了??(le)最??(zui)佳??(jia)角??(jiao)度??(du)??。　　土??(tu)星??(xing)環(huán)??(huan)這?(zhe)個??(ge)“大??(da)圓??(yuan)環(huán)??(huan)”的??(de)直??(zhi)徑??(jing)大??(da)約??(yue)是??(shi)28萬??(wan)公??(gong)里??(li)??，相??(xiang)當??(dang)于??(yu)地??(di)月?(yue)距??(ju)離??(li)的??(de)三?(san)分??(fen)之??(zhi)二??(er)??，但??(dan)是??(shi)土??(tu)星??(xing)環(huán)??(huan)的??(de)平?(ping)均??(jun)垂??(chui)直??(zhi)厚??(hou)度??(du)卻??(que)只??(zhi)有??(you)10米??(mi)左??(zuo)右??(you)??。??所??(suo)以??(yi)說??(shuo)??，土??(tu)星??(xing)的?(de)光??(guang)環(huán)??(huan)“薄??(bo)如??(ru)蟬??(chan)翼??(yi)”??，那??(na)它??(ta)是??(shi)由??(you)什??(shen)么??(me)組??(zu)成??(cheng)的??(de)呢??(ne)？??。