Astronomy Picture of the Day——西面纱星云

Along the Western Veil 
Image Credit & Copyright: Min Xie

Explanation: Delicate in appearance, these filaments of shocked, glowing gas, are draped across planet Earth's sky toward the constellation of Cygnus. They form the western part ofthe Veil Nebula. The Veil Nebula itself is a large supernova remnant, an expanding cloud born of the death explosion of a massive star. Light from the original supernova explosion likely reached Earth over 5,000 years ago. Blasted out in the cataclysmic event, the interstellar shock wave plows through space sweeping up and exciting interstellar material. The glowing filaments are really more like long ripples in a sheet seen almost edge on, remarkably well separated into atomic hydrogen (red) and oxygen (blue-green) gas. Also known as the Cygnus Loop, the Veil Nebula now spans nearly 3 degrees or about 6 times the diameter of the full Moon. While that translates to over 70 light-years at its estimated distance of 1,500 light-years, this telescopic image of the western portion spans about half that distance. Brighter parts of the western Veil are recognized as separate nebulae, including TheWitch's Broom (NGC 6960) along the top of this view and Pickering's Triangle (NGC 6979) below and left.

西面纱星云

这些美丽的炽热丝状云飘浮在地球天空中的天鹅座方向，构成了面纱星云。面纱星云是一颗巨大超新星的残骸，是一颗巨大恒星死亡后产生的膨胀碎片云。来自原始超新星爆炸的光可能在5000多年前到达地球。这次灾难性事件中的星际冲击波穿越了太空，扫过并激发了星际物质。事实上，这些热云更像是我们分层结构中的长长涟漪，并且令人惊讶的是它们只被分为氢（红色）和氧（青色）气体。目前，面纱星云，也被称为天鹅圈，跨度接近3度，约为满月直径的六倍。然而，根据其估计的1500光年距离，星云的大小超过70光年，跨越面纱星云西部的望远镜图像约为一半。在这张照片中，西面纱星云的较亮区域被认为是一个独立的星云，包括顶部的女巫扫帚星云（NGC 6960）和左下角的皮克林三角星云（NGC 6979）。

高清原图地址：

https://apod.nasa.gov/apod/image/1909/veilXie.jpg

近期文章：

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