Copyright:Alberto Pisabarro
中文翻譯:
在遙遠的宇宙中，有一個特別的星系叫作 NGC 6946，它的形狀就像一個大漩渦。所以許多天文學家都叫它消失的煙火星系。還有一個名叫 NGC 6939 的星團在這幅圖片裡，它們一起在天空中閃耀。這張圖片的背後有超過68小時的努力，讓我們可以欣賞到這兩個美麗的天體。這片天空的寬度大約是1度，也就是說可以容納2個滿天的圓月！這些星星是 NGC 6939 的，距離我們有5600光年遠，位於圖片的右下方。而 NGC 6946 則在左上方，它距離我們有2200萬光年！在過去100年裡，NGC 6946裡發現過10顆超新星，最近的一顆是在2017年發現的！相比之下，我們的銀河系大約每100年才有一顆超新星呢！
原文:
Face-on spiral galaxy NGC 6946 and open star cluster NGC 6939 share this cosmic snapshot, composed with over 68 hours of image data captured with a small telescope on planet Earth. The field of view spans spans about 1 degree or 2 full moons on the sky toward the northern constellation Cepheus. Seen through faint interstellar dust couds near the plane of our Milky Way galaxy, the stars of open cluster NGC 6939 are 5,600 light-years in the distance, near bottom right in the frame. Face-on spiral galaxy NGC 6946 is at top left, but lies some 22 million light-years away. In the last 100 years, 10 supernovae have been discovered in NGC 6946, the latest one seen in 2017. By comparison, the average rate of supernovae in our Milky Way is about 1 every 100 years or so. Of course, NGC 6946 is also known as The Fireworks Galaxy.
來源:NASA每日圖片
