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學習快評丨qibao666888　　在??(zai)北??(bei)京??(jing)天??(tian)文??(wen)館??(guan)?，科??(ke)普??(pu)專?(zhuan)家??(jia)介??(jie)紹??(shao)?，土??(tu)星??(xing)環(huán)??(huan)的?(de)“消??(xiao)失?(shi)”并??(bing)非??(fei)真??(zhen)正??(zheng)意??(yi)義?(yi)上??(shang)的??(de)消?(xiao)失??(shi)?，而??(er)是?(shi)天??(tian)穹??(qiong)之??(zhi)上??(shang)的??(de)一??(yi)場??(chang)精??(jing)彩??(cai)的??(de)光??(guang)影??(ying)魔??(mo)術(shù)??(shu)??。??早??(zao)在??(zai)1612年??(nian)?，意??(yi)大??(da)利??(li)科??(ke)學??(xue)家??(jia)伽??(jia)利??(li)略??(lve)就??(jiu)首??(shou)次?(ci)觀??(guan)測??(ce)到??(dao)土??(tu)星??(xing)環(huán)?(huan)“消?(xiao)失??(shi)”現(xiàn)??(xian)象??(xiang)??。　　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)？??。