2025年7月19日
Messier 6
Image Credit & Copyright: Xinran Li
Explanation: The sixth object in Charles Messier’s famous catalog of things which are not comets, Messier 6 is a galactic or open star cluster. A gathering of 100 stars or so, all around 100 million years young, M6 lies some 1,600 light-years away toward the central Milky Way in the constellation Scorpius. Also cataloged as NGC 6405, the pretty star cluster’s outline suggests its popular moniker, the Butterfly Cluster. Surrounded by diffuse reddish emission from the region’s hydrogen gas the cluster’s mostly hot and therefore blue stars are near the center of this colorful cosmic snapshot. But the brightest cluster member is a cool K-type giant star. Designated BM Scorpii it shines with a yellow-orange hue, seen near the end of one of the butterfly’s antennae. This telescopic field of view spans nearly 2 Full Moons on the sky. That’s 25 light-years at the estimated distance of Messier 6.
Tomorrow’s picture: light-weekend
说明: 在梅西耶著名的”非彗星天体“星表里，编序第六的Ｍ6，是个疏散星团（亦称银河星团）。拥有100颗上下、稚龄约为1亿年的成员星之M6，座落于银河系中心的天蝎座方向，约1,600光年远处。此外，亦拥有编录号NGC 6405的美丽星团M6，因其外观而有蝴蝶星团的称号。周围环拱着弥漫泛红氢气辐射，其内有炽热泛蓝成员星的M6，位于这幅色彩缤纷宇宙影像的中心附近。不过，它最明亮的成员星却是一颗低温的K型巨星。这颗编录号为天蝎BM（BM Scorpii）的亮星，则在蝴蝶的触须之一的尾端散发黄橙色的辉光。这片望远镜视野涵盖了将近2个满月的天区；以M6的估计距离来换算，其跨幅约为25光年。
明日的图片： light-weekend
