貓(mao)眼星(xing)云,是天龍座(zuo)的(de)(de)一個(ge)行星(xing)狀星(xing)云,因為形狀長得(de)(de)像(xiang)貓(mao)的(de)(de)眼睛而得(de)(de)名。從(cong)哈(ha)勃(bo)太空望遠鏡拍得(de)(de)的(de)(de)圖(tu)像(xiang)顯(xian)示,貓(mao)眼星(xing)云擁有繩(sheng)結(jie)、噴柱(zhu)、弧(hu)形等各種形狀的(de)(de)結(jie)構(gou)。于1786年(nian)2月15日由威(wei)廉·赫歇爾首先(xian)發現,是已(yi)知的(de)(de)結(jie)構(gou)最(zui)復(fu)雜的(de)(de)星(xing)云之一。
貓眼(yan)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)(yun)(yun)(yun)(Cat’sEyeNebula)為(wei)一行星(xing)(xing)(xing)(xing)(xing)(xing)(xing)狀(zhuang)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)(yun)(yun)(yun),位于天(tian)(tian)龍座。這(zhe)個(ge)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)(yun)(yun)(yun)特別的(de)地方,在(zai)于其結構幾乎是(shi)所有(you)(you)有(you)(you)記錄的(de)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)(yun)(yun)(yun)當中(zhong)最為(wei)復雜的(de)一個(ge)。這(zhe)個(ge)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)(yun)(yun)(yun)于1786年2月15日由(you)威(wei)廉·赫(he)歇爾(WilliamHerschel)首(shou)先(xian)發(fa)現(xian)。至1864年,英(ying)國業余天(tian)(tian)文學家威(wei)廉·赫(he)金斯(WilliamHuggins)為(wei)貓眼(yan)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)(yun)(yun)(yun)作了光譜(pu)分(fen)析,也是(shi)首(shou)次將(jiang)光譜(pu)分(fen)析技術用于星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)(yun)(yun)(yun)上。現(xian)代(dai)的(de)研究揭開不少有(you)(you)關貓眼(yan)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)(yun)(yun)(yun)的(de)謎團(tuan),有(you)(you)人認為(wei)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)(yun)(yun)(yun)結構之所以復雜,是(shi)來(lai)自其連星(xing)(xing)(xing)(xing)(xing)(xing)(xing)系(xi)統中(zhong)主星(xing)(xing)(xing)(xing)(xing)(xing)(xing)的(de)噴發(fa)物質,但(dan)至今尚未有(you)(you)證據指(zhi)其中(zhong)心(xin)恒星(xing)(xing)(xing)(xing)(xing)(xing)(xing)擁有(you)(you)伴星(xing)(xing)(xing)(xing)(xing)(xing)(xing)。另外,兩個(ge)有(you)(you)關星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)(yun)(yun)(yun)化學物質量度的(de)結果(guo)出(chu)現(xian)重大差異,其原因目前仍不明。
這(zhe)(zhe)個星(xing)云(yun)看(kan)起(qi)來有點像(xiang)(xiang)貓(mao)的(de)(de)眼(yan)(yan)睛。漂(piao)亮的(de)(de)貓(mao)眼(yan)(yan)星(xing)云(yun)位于離地球約3000光(guang)年遠的(de)(de)星(xing)際(ji)空(kong)(kong)間中。作為經典的(de)(de)行星(xing)狀星(xing)云(yun),貓(mao)眼(yan)(yan)星(xing)云(yun)是與太(tai)陽相似恒星(xing)生命短暫而輝煌(huang)的(de)(de)閉幕(mu)式。星(xing)云(yun)的(de)(de)垂死中央星(xing)會通(tong)過不斷(duan)的(de)(de)抽搐將(jiang)其外(wai)層物質(zhi)拋擲到(dao)宇宙(zhou)空(kong)(kong)間中,形(xing)成一(yi)個簡(jian)潔的(de)(de),由(you)塵埃(ai)組成的(de)(de)同心圓外(wai)殼。但是它美麗的(de)(de)內部結構更(geng)為復雜,其形(xing)成機制還沒有得(de)到(dao)很(hen)好(hao)的(de)(de)了解。由(you)哈勃空(kong)(kong)間望(wang)遠鏡拍攝(she)的(de)(de)數字影像(xiang)(xiang)看(kan)起(qi)來十分(fen)清楚,這(zhe)(zhe)只宇宙(zhou)級大眼(yan)(yan)睛的(de)(de)實際(ji)寬度要在0.5光(guang)年以上。