2025年5月23日
NGC 6366 vs 47 Ophiuchi
Image Credit & Copyright: Massimo Di Fusco
Explanation: Most globular star clusters roam the halo of our Milky Way galaxy, but globular cluster NGC 6366 lies close to the galactic plane. About 12,000 light-years away toward the constellation Ophiuchus, the cluster’s starlight is dimmed and reddened by the Milky Way’s interstellar dust when viewed from planet Earth. As a result, the stars of NGC 6366 look almost golden in this telescopic scene, especially when seen next to relatively bright, bluish, and nearby star 47 Ophiuchi. Compared to the hundred thousand stars or so gravitationally bound in distant NGC 6366, 47 Oph itself is a binary star system a mere 100 light-years away. Still, the co-orbiting stars of 47 Oph are too close together to be individually distinguished in the image.
Tomorrow’s picture: Deimos before sunrise
星团NGC 6366与蛇夫47星
影像提供与版权: Massimo Di Fusco
说明: 大多数的球状星团远在银河系的银晕里漫游，不过，球状星团NGC 6366所在的位置很接近银河盘面。所以从地球看出去，这个位于蛇夫座方向、距离约12,000光年远的星团之星光，受到银河系星际尘埃的消光与红化。因此在这幅望远镜影像里，NGC 6366成员星的色泽几乎呈金黄色，也与视野附近较明亮的泛蓝蛇夫47星（47 Oph）形成鲜明的对比。不过，相对于受到重力束缚而聚集成团的数十万颗遥远NGC 6366成员星，蛇夫47星内的双星距离我们只有100光年。话虽如此，相互绕行的47 Oph之双星非常密近，这幅影像并未能加以解析。
明日的图片: Deimos before sunrise
