心宿增四星云的广角影像
影像来源与版权:Mario Cogo (Galax Lux)

说明:环绕恒星系统心宿增四的彩色星云是距离我们最近的恒星形成区之一。心宿增四本身是一个双星系统,在这幅影像中央左侧的蓝色反射星云内可见。这个恒星系统距离我们仅400光年远,以其多彩的环绕物质而著名,包括一个红色发射星云和许多浅棕色、深棕色的尘埃带。在心宿增四分子云系统的左下方附近可见黄色的心宿二,而遥远但恰巧同向的球状星团M4则在心宿二右侧可见。位于影像顶部附近的是蓝色马头星云IC 4592。环绕蓝色马头眼睛和影像周围其他恒星的蓝光来自由细小尘埃构成的反射星云。位于这幅特征影像右侧的就是编录号为Sharpless 1的反射星云。在这里,尘埃涡流附近的明亮恒星使周围的反射星云呈现蓝色。尽管我们使用一台小型望远镜朝向蛇夫座、天蝎座和人马座方向,就能看到大部分特征,但是想要看到如上图所示的尘埃漩涡复杂细节,唯一的方法就是使用一台长曝光相机。
翻译:北京天文馆

Rho Ophiuchi Wide Field
Image Credit & Copyright: Mario Cogo (Galax Lux)

Explanation: The colorful clouds surrounding the star system Rho Ophiuchi compose one of the closest star forming regions. Rho Ophiuchi itself is a binary star system visible in the blue reflection nebula just to the left of the image center. The star system, located only 400 light years away, is distinguished by its multi-colored surroundings, which include a red emission nebula and numerous light and dark brown dust lanes. Near the lower left of the Rho Ophiuchi molecular cloud system is the yellow star Antares, while a distant but coincidently-superposed globular cluster of stars, M4, is visible just to the right of Antares. Near the image top lies IC 4592, the Blue Horsehead nebula. The blue glow that surrounds the Blue Horsehead’s eye — and other stars around the image — is a reflection nebula composed of fine dust. On the featured image right is a geometrically angled reflection nebula cataloged as Sharpless 1. Here, the bright star near the dust vortex creates the light of surrounding reflection nebula. Although most of these features are visible through a small telescope pointed toward the constellations of Ophiuchus, Scorpius, and Sagittarius, the only way to see the intricate details of the dust swirls, as featured above, is to use a long exposure camera.
Astronomy Picture of the Day 05/13/2019