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學(xué)習(xí)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)??，看??(kan)上??(shang)去??(qu)美??(mei)麗??(li)的??(de)土??(tu)星?(xing)光?(guang)環(huán)??(huan)??，實??(shi)際??(ji)上?(shang)是??(shi)由??(you)無??(wu)數(shù)??(shu)水?(shui)冰?(bing)顆??(ke)粒??(li)、巖??(yan)石??(shi)碎?(sui)片?(pian)和??(he)塵?(chen)埃??(ai)構(gòu)??(gou)成??(cheng)??，規(guī)??(gui)模?(mo)超??(chao)級??(ji)龐?(pang)大??(da)??，但??(dan)是??(shi)厚??(hou)度??(du)有??(you)的??(de)地??(di)方??(fang)是??(shi)摩??(mo)天??(tian)大??(da)樓?(lou)??，有??(you)的??(de)地??(di)方??(fang)卻??(que)只??(zhi)有??(you)平??(ping)房??(fang)那??(na)么??(me)高??(gao)??，平??(ping)均??(jun)下??(xia)來??(lai)也??(ye)就??(jiu)十??(shi)多??(duo)米??(mi)??。??　　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(dāng)??(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)？??。