NGC 7331及更远
(原标题: NGC 7331 and Beyond)
2023-09-14
浏览次数: 20
巨大而美丽的螺旋星系NGC 7331经常被吹捧为与我们的银河系类似。NGC 7331位于飞马座北部，距离我们大约5000万光年，它很早就被认为是一个螺旋状星云，实际上是查尔斯·梅西耶著名的18世纪星表中没有包括的较亮的星系之一。由于星系的圆盘向我们的视线倾斜，长时间的望远镜曝光通常会产生强烈的深度感。在这张清晰的图像中，位于美丽的宇宙岛之外的星系进一步增强了这种效果。最突出的背景星系大约是NGC 7331视大小的十分之一，因此距离大约是它的十倍。它们与NGC 7331在天空中的近距离排列只是偶然发生的。徘徊在银河系平面之上，这个引人注目的视觉星系群被一些人称为鹿舔群。
查看原文解释
Big, beautiful spiral galaxy NGC 7331 is often touted as an analog to our own Milky Way. About 50 million light-years distant in the northern constellation Pegasus, NGC 7331 was recognized early on as a spiral nebula and is actually one of the brighter galaxies not included in Charles Messier's famous 18th century catalog. Since the galaxy's disk is inclined to our line-of-sight, long telescopic exposures often result in images that evokes a strong sense of depth. The effect is further enhanced in this sharp image by galaxies that lie beyond the gorgeous island universe. The most prominent background galaxies are about one tenth the apparent size of NGC 7331 and so lie roughly ten times farther away. Their close alignment on the sky with NGC 7331 occurs just by chance. Lingering above the plane of the Milky Way, this striking visual grouping of galaxies is known to some as the Deer Lick Group.
© Ian Gorenstein