charles 2009-3-23 11:38
美國亞利桑那州上空的星雲
Star Clouds over Arizona
[img]http://i13.tinypic.com/2v3iqds.jpg[/img]
影像版權與提供: Ulrich Beinert
[color=navy]Explanation:[/color]
[color=dimgray]The clouds in the foreground are much different than the clouds in the background. In the foreground are a photogenic deck of Earth-based water clouds. The long exposure used to create the above photograph makes the light from the left, reflected from Phoenix, Arizona, USA, appear like a sunset. Far in the distance, however, are star clouds from the disk of our Milky Way Galaxy. Billions of stars like our Sun live there, circling our Galactic center every 200 million years. Contrast between the water clouds and the star clouds has been digitally enhanced. Between the two, visible on the upper right, is the planet Jupiter. [/color]
[color=navy]說明:[/color]
[color=dimgray]影像前景的雲和背景的雲是截然不同的。前方的是地球亮麗之水氣雲層，因為拍攝上面這幅影像時使用了長曝光，左方來自美國．亞利桑那州鳳凰城 (Phoenix)的燈光從雲層反射，造成類似日落時分的景象；遙遠的後方則為我們銀河系盤面上的星雲。數十億顆恆星聚成的這些星雲，每次繞行銀河中心要用上二億年。水氣雲及星雲的對比經過數位強化。影像右上角可見到位在這二種"雲"之間的木星。[/color]
[size=2]資料來源: Scientific American
Department of Physics, NCKU[/size][color=white][size=1]
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