vicky3 2009-8-14 10:52
獵戶座大星雲和獵戶座LL星
LL Ori and the Orion Nebula
[img]http://i15.tinypic.com/2i07p6d.jpg[/img]
影像提供 NASA, ESA, and The Hubble Heritage Team
[color=navy]Explanation: [/color]
[color=dimgray]This esthetic close-up of cosmic clouds and stellar winds features LL Orionis, interacting with the Orion Nebula flow. Adrift in Orion's stellar nursery and still in its formative years, variable star LL Orionis produces a wind more energetic than the wind from our own middle-aged Sun. As the fast stellar wind runs into slow moving gas a shock front is formed, analogous to the bow wave of a boat moving through water or a plane traveling at supersonic speed. The small, arcing, graceful structure just above and left of center is LL Ori's cosmic bow shock, measuring about half a light-year across. The slower gas is flowing away from the Orion Nebula's hot central star cluster, the Trapezium, located off the upper left corner of the picture. In three dimensions, LL Ori's wrap-around shock front is shaped like a bowl that appears brightest when viewed along the "bottom" edge. The beautiful picture is part of a large mosaic view of the complex stellar nursery in Orion, filled with a myriad of fluid shapes associated with star formation. [/color]
[color=navy]說明:[/color]
[color=dimgray]那些看起來很美麗的宇宙雲及星際風讓 獵戶座LL星(LL Orionis)更添風采，與獵戶座星雲(Orion Nebula)的氣流之間互相作用。 獵戶座LL星在獵戶座的星星形成區域中，並且仍在剛形成的區域，獵戶座LL星產生恆星風，能量高於我們的太陽所發出的 太陽風。 當高速的星際風吹進很緩慢流動的氣體，一個衝擊波將會形成。就像是 船頭震波，或是飛機以超音速的速度進行。 一個小的，呈現弧狀結構就在照片中的左方中央的位置，也就是獵戶座LL星船頭震波，大約有半個光年。 獵戶座星雲內的氣體正緩緩地從中央的熾熱恆星 (四合星, Trapezium)吹出，位於照片上方左邊角落。 如果從三維的角度去看，獵戶座LL星彎曲的震波就像是一個碗形，如果從底部去看，會是最亮的。 這張絢麗的照片只是獵戶座複雜的星星形成區域的一部份，充滿各式各樣的星星形成的 流線形狀。 [/color]
[size=2]資料來源: Scientific American
Department of Physics, NCKU[/size][color=white][size=1]
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