貓眼(yan)星(xing)(xing)云,是天龍座的(de)一(yi)個(ge)行星(xing)(xing)狀星(xing)(xing)云,因為(wei)形狀長得(de)(de)像貓的(de)眼(yan)睛而得(de)(de)名。從哈勃太空望遠鏡拍得(de)(de)的(de)圖像顯示,貓眼(yan)星(xing)(xing)云擁有(you)繩(sheng)結(jie)、噴(pen)柱、弧形等各種形狀的(de)結(jie)構。于1786年2月(yue)15日(ri)由(you)威廉·赫歇爾首先發現,是已知的(de)結(jie)構最復雜的(de)星(xing)(xing)云之(zhi)一(yi)。
貓(mao)眼(yan)(yan)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)(Cat’sEyeNebula)為一(yi)行星(xing)(xing)(xing)(xing)(xing)(xing)(xing)狀(zhuang)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun),位于天龍座。這個(ge)(ge)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)特別的(de)(de)地方,在于其(qi)結(jie)構(gou)幾乎是(shi)所(suo)(suo)有(you)(you)有(you)(you)記錄的(de)(de)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)當中最為復(fu)雜的(de)(de)一(yi)個(ge)(ge)。這個(ge)(ge)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)于1786年2月15日由(you)威廉·赫(he)歇爾(WilliamHerschel)首(shou)(shou)先發現(xian)。至1864年,英國(guo)業余天文學(xue)(xue)家威廉·赫(he)金斯(WilliamHuggins)為貓(mao)眼(yan)(yan)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)作了光譜分(fen)析,也是(shi)首(shou)(shou)次將光譜分(fen)析技術用于星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)上。現(xian)代的(de)(de)研究揭開不少有(you)(you)關貓(mao)眼(yan)(yan)星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)的(de)(de)謎團,有(you)(you)人認為星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)結(jie)構(gou)之所(suo)(suo)以復(fu)雜,是(shi)來自其(qi)連星(xing)(xing)(xing)(xing)(xing)(xing)(xing)系統中主星(xing)(xing)(xing)(xing)(xing)(xing)(xing)的(de)(de)噴發物質,但(dan)至今尚未有(you)(you)證據指其(qi)中心(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)(ge)有(you)(you)關星(xing)(xing)(xing)(xing)(xing)(xing)(xing)云(yun)(yun)(yun)化學(xue)(xue)物質量度的(de)(de)結(jie)果出現(xian)重大差異,其(qi)原(yuan)因目前仍不明。
這個星(xing)(xing)(xing)云(yun)(yun)(yun)看(kan)起來(lai)有(you)點像貓(mao)的(de)眼睛。漂亮的(de)貓(mao)眼星(xing)(xing)(xing)云(yun)(yun)(yun)位于離地球約3000光(guang)年(nian)遠的(de)星(xing)(xing)(xing)際空(kong)(kong)間(jian)中(zhong)。作為經典的(de)行星(xing)(xing)(xing)狀(zhuang)星(xing)(xing)(xing)云(yun)(yun)(yun),貓(mao)眼星(xing)(xing)(xing)云(yun)(yun)(yun)是與太陽相似恒星(xing)(xing)(xing)生命短暫而輝煌(huang)的(de)閉幕式(shi)。星(xing)(xing)(xing)云(yun)(yun)(yun)的(de)垂死中(zhong)央星(xing)(xing)(xing)會通過不斷的(de)抽(chou)搐將其(qi)外(wai)層物質(zhi)拋擲到宇(yu)宙(zhou)空(kong)(kong)間(jian)中(zhong),形成一個簡潔的(de),由塵埃組成的(de)同心圓(yuan)外(wai)殼。但是它美麗(li)的(de)內部(bu)結構更為復雜,其(qi)形成機制還(huan)沒有(you)得到很好的(de)了解。由哈勃空(kong)(kong)間(jian)望遠鏡拍攝的(de)數(shu)字影像看(kan)起來(lai)十分清楚,這只宇(yu)宙(zhou)級大眼睛的(de)實際寬度要(yao)在0.5光(guang)年(nian)以上。