Astronomy Picture of the Day——心宿二附近的暗尘与彩云

Dark Dust and Colorful Clouds near Antares 
Image Credit: David McGarvey

Explanation: Why is the sky near Antares and Rho Ophiuchi so dusty yet colorful? The colors result from a mixture of objects and processes. Fine dust illuminated from the front by starlight produces blue reflection nebulae. Gaseous clouds whose atoms are excited by ultraviolet starlight produce reddish emission nebulae. Backlit dust clouds block starlight and so appear dark. Antares, a red supergiant and one of the brighter stars in the night sky, lights up the yellow-red clouds on the lower left of the featured image. Rho Ophiuchi lies at the center of the blue nebula near the top. The distant globular cluster M4 is visible to the right of Antares. These star clouds are even more colorful than humans can see, emitting light across the electromagnetic spectrum.

心宿二附近的暗尘与彩云

为什么心宿二和心宿四附近的天空满是尘埃但是却色彩缤纷？因为这些颜色是由天体演化过程的产物所展示的。受到星光照耀的细微尘埃产生了蓝色反射星云。原子受到紫外线激发而使气体云组成了红色发射星云。背光的尘埃云遮挡了星光，所以它看起来很暗。心宿二是一颗红超巨星，是夜空中最亮的恒星之一，它照亮了这幅图像左下方的黄色云团。心宿四位于图像顶部蓝色星云的中心。可以在心宿二右侧发现球状星团M4。这些星云发出的光遍布整个电磁光谱，实际上比我们所能看到的还要绚烂多彩。

高清原图地址：

https://apod.nasa.gov/apod/image/1908/AntaresRho_McGarvey_2200.jpg

近期文章：

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