大神級稀罕星云照：古姆星云

The Gum Nebula is so large and close it is actually hard to see. This interstellar expanse of glowing hydrogen gas frequently evades notice because it spans 35 degrees -- over 70 full Moons -- while much of it is quite dim. This featured spectacular 90-degree wide mosaic, however, was designed to be both wide and deep enough to bring up the Gum -- visible in red on the right. The image was acquired late last year with both the foreground -- including Haba Snow Mountain -- and the background -- including the Milky Way's central band -- captured by the same camera and from the same location in Shangri-La, Yunnan, China. The Gum Nebula is so close that we are only about 450 light-years from the front edge, while about 1,500 light-years from the back edge. Named for a cosmic cloud hunter, Australian astronomer Colin Stanley Gum (1924-1960), the origin of this complex nebula is still being debated. A leading theory for the origin of the Gum Nebula is that it is the remnant of a million year-old supernova explosion, while a competing theory holds that the Gum is a molecular cloud shaped over eons by multiple supernovas and the outflowing winds of several massive stars.?

古姆星云非常大，離我們非常近，實際上很難看到。這片在星際間大面積伸展的發(fā)光氫氣云經(jīng)常被忽略，因為它的直徑約35度——相當于70多個滿月，而其中大部分都相當暗淡。不過，這幅90度寬的壯觀拼接照拍得既廣角又深度，足以展示出古姆星云，也就是在畫面右側可見的紅色。這幅照片是去年晚些時候在中國云南香格里拉拍攝的，前景（包括哈巴雪山）和背景（包括銀河）在同一地點用同一臺相機拍攝。古姆星云離我們太近了，我們距離它的前緣只有450光年，而距離它的后緣也只有1500光年。這個復雜的星云以一位宇宙云獵人——澳大利亞天文學家科林·斯坦利·古姆（1924-1960）的名字命名，其起源仍有爭議。關于古姆星云起源的一個主要理論是，它是百萬年前超新星爆炸的殘余物；而另一個與之競爭的理論認為，古姆星云是被多重超新星和多顆大質量恒星的外流星風在數(shù)十億年間“塑造”出的分子云。