智利火山上空的南十字

2021年01月25日

Southern Cross over Chilean Volcano
Image Credit & Copyright: Tomáš Slovinský

Explanation: Have you ever seen the Southern Cross? This famous four-star icon is best seen from Earth’s Southern Hemisphere. The featured image was taken last month in Chile and captures the Southern Cross just to the left of erupting Villarrica, one of the most active volcanos in our Solar System. Connecting the reddest Southern Cross star Gacrux through the brightest star Acrux points near the most southern location in the sky: the South Celestial Pole (SCP), around which all southern stars appear to spin as the Earth turns. In modern times, no bright star resides near the SCP, unlike in the north where bright Polaris now appears near the NCP. Extending the Gacrux – Acrux line still further (from about four to about seven times their angular separation) leads near the Small Magellanic Cloud, a bright satellite galaxy of our Milky Way Galaxy. The Southern Cross asterism dominates the Crux constellation, a deeper array of stars that includes four Cepheid variable stars visible to the unaided eye. Just above the volcano in the image, and looking like a dark plume, is the Coalsack Nebula, while the large red star-forming Carina Nebula is visible on the upper left.

Portal Universe: Random APOD Generator

Tomorrow’s picture: detective hubble

智利火山上空的南十字
影像提供与版权: Tomáš Slovinský

说明: 你看过南十字吗？观看这个这个著名星座的最佳地点，是地球的南半球。在上面这幅这个月稍早摄于智利的主题影像里，南十字悬在太阳系最活跃火山之一、爆发中的维雅利卡火山之左方。其中，最红的十字架一和最明亮的十字架二之连线，指向天空最南的南天极（SCP），而随着地球自转，南天的恒星看似全都在旋绕此点。在近代里，南天极附近并没有像北极星这种亮星。沿十字架一和十字架二的连线向外延伸约4到7倍张角的距离，可见到我们银河系明亮伴星系之一的小麦哲伦星系。南十字 星宫是南十字座最吸睛的天体，而在此星座肉眼可见的恒星之中，更包括4颗造父变星。在火山上方看似黝黑烟尘的结构，其实是煤袋星云。此外，在影像的左上角，可见到南天大型泛红的恒星形成区船底座星云。

宇宙传送门: 随机天文·每日一图（APOD）生成器

明日的图片: detective hubble