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學(xué)習(xí)快評丨qibao666888　　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)？??　　北??(bei)京??(jing)天??(tian)文??(wen)館??(guan)科??(ke)普??(pu)教??(jiao)育??(yu)部?(bu)副??(fu)研??(yan)究?(jiu)館??(guan)員??(yuan)曹??(cao)軍??(jun)表??(biao)示??(shi)?，如??(ru)果??(guo)持??(chi)續(xù)??(xu)觀??(guan)察??(cha)土??(tu)星??(xing)?，會?(hui)發(fā)??(fa)現(xiàn)??(xian)光??(guang)環(huán)?(huan)朝??(chao)向??(xiang)地??(di)球??(qiu)的??(de)角??(jiao)度??(du)是??(shi)在??(zai)不??(bu)斷??(duan)變??(bian)化??(hua)的??(de)?，大??(da)概??(gai)十??(shi)幾?(ji)年??(nian)會??(hui)完??(wan)成??(cheng)一??(yi)個??(ge)輪??(lun)回??(hui)??。??今??(jin)年?(nian)3月??(yue)份??(fen)?，地??(di)球??(qiu)正??(zheng)好??(hao)在??(zai)光??(guang)環(huán)??(huan)的??(de)平??(ping)面??(mian)上??(shang)?，因??(yin)此??(ci)看??(kan)上??(shang)去??(qu)就??(jiu)好?(hao)像??(xiang)光??(guang)環(huán)??(huan)消??(xiao)失??(shi)了??(le)一??(yi)樣??(yang)??。。