参宿七和女巫头星云
(原标题: Rigel and the Witch Head Nebula)
2024-10-31
浏览次数: 18
在星光的照耀下，这张怪异的脸在黑暗中闪耀着弯曲的轮廓，让人想起它的通俗名字——女巫头星云。事实上，这张引人入胜的望远镜照片给人的印象是一个女巫凝视着猎户座明亮的超巨星参宿七。女巫头星云的正式名称是IC 2118，它的跨度约为50光年，由反射参宿七星光的星际尘埃颗粒组成。女巫头星云的颜色不仅是由参宿七强烈的蓝光引起的，而且因为尘埃颗粒比红光更有效地散射蓝光。同样的物理过程导致地球白天的天空呈现蓝色，尽管地球大气中的散射物是氮和氧分子。参宿七和这个尘土飞扬的宇宙老妪距离我们大约800光年远。今晚你可能仍然会在你的邻居看到一些女巫，所以有一个安全快乐的万圣节！
查看原文解释
By starlight, this eerie visage shines in the dark with a crooked profile evoking its popular name, the Witch Head Nebula. In fact, this entrancing telescopic portrait gives the impression that a witch has fixed her gaze on Orion's bright supergiant star Rigel. More formally known as IC 2118, the Witch Head Nebula spans about 50 light-years and is composed of interstellar dust grains reflecting Rigel's starlight. The color of the Witch Head Nebula is caused not only by Rigel's intense blue light, but because the dust grains scatter blue light more efficiently than red. The same physical process causes Earth's daytime sky to appear blue, although the scatterers in Earth's atmosphere are molecules of nitrogen and oxygen. Rigel and this dusty cosmic crone are about 800 light-years away. You may still see a few witches in your neighborhood tonight though, so have a safe and Happy Halloween!
© Simone Curzi