南冕座的恒星和尘埃

2023年6月22日

Stars and Dust across Corona Australis
Image Credit & Copyright: Alessandro Cipolat Bares

Explanation: Cosmic dust clouds cross a rich field of stars in this telescopic vista near the northern boundary of Corona Australis, the Southern Crown. Part of a sprawling molecular cloud complex this star forming region is a mere 500 light-years away. That’s about one third the distance of the more famous stellar nursery known as the Orion Nebula. The 2 degree wide frame would span 15 light-years at the clouds’ estimated distance. Mixed with bright nebulosities the dust clouds effectively block light from more distant background stars in the Milky Way and obscure from view embedded stars still in the process of formation. Large dark nebula Bernes 157 is on the left. To its right are a group of pretty reflection nebulae cataloged as NGC 6726, 6727, 6729, and IC 4812. Their characteristic blue color is produced as light from hot stars is reflected by the cosmic dust. The more compact NGC 6729 surrounds young variable star R Coronae Australis. Just below it, filamentary arcs and loops are identified as Herbig Haro objects associated with energetic newborn stars. In fact, at the heart of this area lies the Coronet Cluster, one of the nearest and most active star forming regions.

Tomorrow’s picture: the condor galaxy

南冕座的恒星和尘埃
影像提供与版权: Alessandro Cipolat Bares

说明: 这片望远镜景观的主题是南冕座北缘的繁星和尘埃云。这个为一个广袤分子云复合体成员的恒星形成区，距离我们仅有500光年远。也就是说，它的距离约莫是著名猎户大星云的3分之1。以星云所在的距离来换算，这片2度宽的视野涵盖了15光年的区域。而这些夹杂着明亮星云的尘埃云，几乎完全遮住后方银河背景恒星及其内部仍处在形成阶段的恒星之星光。影像左侧的大型暗星云为Bernes 157，其右方的成群美丽反射星云，编录号分别为NGC 6726、6727、6729、和IC 4812。它们特征性的泛蓝色泽，来自受到尘埃反射的炽热恒星之星光。较紧实的NGC 6729，则包覆在年轻变星南冕座R的周围。紧贴在它下方的丝状光弧和环状结构，为活跃新恒星所产生的赫比格-哈罗天体。事实上，座落在这个区域核心的南冕星团，是离我们最近最活跃的恒星形成区之一。

明日的图片: the condor galaxy