马头星云

2019 October 6

The Horsehead Nebula
Image Credit & Copyright: José Jiménez Priego

Explanation: The Horsehead Nebula is one of the most famous nebulae on the sky. It is visible as the dark indentation to the red emission nebula in the center of the above photograph. The horse-head feature is dark because it is really an opaque dust cloud that lies in front of the bright red emission nebula. Like clouds in Earth’s atmosphere, this cosmic cloud has assumed a recognizable shape by chance. After many thousands of years, the internal motions of the cloud will surely alter its appearance. The emission nebula’s red color is caused by electrons recombining with protons to form hydrogen atoms. On the image left is the Flame Nebula, an orange-tinged nebula that also contains filaments of dark dust. Just to the lower left of the Horsehead nebula featured picture is a blueish reflection nebulae that preferentially reflects the blue light from nearby stars.

马头星云
影像提供与版权: José Jiménez Priego

说明: 马头星云是地球天空中最著名的星云之一。这张影像中心的红色发射星云上，那片黝黑斑块就是马头星云。而「马头」会如此黝黑，源自它是这片明亮泛红发射星云前方的不透光尘埃云。类似地球大气中的云朵，这团宇宙云只是恰巧有个我们很熟悉的形状。再经过数千年，星云内部的运动定然会改变它的外观。发射星云的泛红色泽，是来自电子和质子复合形成氢原子时所发出的光。这张主题影像左方的橙红星云，则是含有丝状黝黑尘埃的火焰星云。紧贴在马头星云左下方的泛蓝反射星云，其色泽源自它偏好的反射大量邻近恒星星光中的蓝光。