Astronomy Picture of the Day——蝘蜓座II号暗星云
Chamaeleon II Dark Cloud
Image Credit & Copyright: Don Goldman
Explanation: A small constellation hiding near the south celestial pole, The Chamaeleon boasts no bright stars. Stars are forming within its constellation boundaries though, in a complex of dark, dusty molecular clouds. Some 500 light-years distant, the Chamaeleon II dark nebula inhabits this view where the cosmic dust clouds standout mostly in silhouette against the starry southern sky. The telescopic frame is about the angular size of a Full Moon and so spans about 5 light-years at the dark cloud's estimated distance. Scattered near center a telltale reddish glow from identified Herbig-Haro objects is seen in the sharp image, jets of shocked glowing gas emanating from recently formed stars.
蝘蜓座II号暗星云
蝘蜓座是隐藏在南天极附近的一个星座，虽然没有明亮的恒星存在，但是，它的恒星正在星座内一个满是尘埃的暗分子云复杂体中形成。这幅影像中的蝘蜓座II号暗星云距离地球约500光年，这个宇宙尘埃云在南天星空的衬托下形成了剪影。这幅望远镜影像的角直径大约是一个满月的大小，因此，以暗星云的估计距离来计算，其跨度约为5光年。在这张清晰的影像中，赫比格-哈罗天体发出的红色光芒在靠近中心的地方分散开来，这是由新近形成的恒星发出的激发态炽热气体喷射而成。
参考文献：
https://apod.nasa.gov/apod/image/1908/Cha-II-Cloud-WebAstroDon.jpg
近期文章：
Astronomy Picture of the Day——土卫二上的虎纹