一个超越恒星、气体和尘埃的星系
(原标题: A Galaxy Beyond Stars, Gas, Dust)
2022-10-19
浏览次数: 20
我们敢相信自己的眼睛吗？当我们看到太空的图像时，我们常常怀疑它们是否“真实”，而最好的答案也常常是不同的。在这种情况下，场景看起来就像我们的眼睛看到的一样，因为它是使用RGB（红、绿、蓝）滤镜获得的，就像我们眼睛中的视锥细胞一样，除了收集光19个小时，而不是一秒钟的一小部分。这幅特色图像是在美国加利福尼亚州内华达山脉使用直径24英寸的望远镜拍摄的，历时6个晚上。中央明亮的螺旋星系（NGC 7497）看起来就像被一个太空幽灵的怪异卷尾所抓住，这就是诀窍所在。这个星系实际上距离我们5900万光年，而这个星云是MBM 54，距离我们不到1000光年，这使它成为我们银河系中最近的冷气体云和尘埃云——星系卷云。这两个星座都位于飞马座，在秋天从北纬地区的高空可以看到。
查看原文解释
Do we dare believe our eyes? When we look at images of space, we often wonder whether they are "real", and just as often the best answer varies. In this case, the scene appears much as our eyes would see it, because it was obtained using RGB (Red, Green, Blue) filters like the cone cells in our eyes, except collecting light for 19 hours, not a fraction of a second. The featured image was captured over six nights, using a 24-inch diameter telescope in the Sierra Nevada Mountains, in California, USA. The bright spiral galaxy at the center (NGC 7497) looks like it is being grasped by an eerie tendril of a space ghost, and therein lies the trick. The galaxy is actually 59 million light years away, while the nebulosity is MBM 54, less than one thousand light years away, making it one of the nearest cool clouds of gas and dust -- galactic cirrus -- within our own Milky Way Galaxy. Both are in the constellation of Pegasus, which can be seen high overhead from northern latitudes in the autumn.
© Howard Trottier; Text: Emily Rice