球状星团Terzan 5
影像来源与版权:Nick Risinger (skysurvey.org), DSS, Hubble, NASA, ESA, ESO; Music: Johan B. Monell

说明:球状星团曾经是银河系的主宰。在我们星系刚形成的早期,或许有数千个球状星团在我们星系内漫游。不过,如今只剩下不到200个。在亘古以来,许多球状星团在和其他星团或银河中心的宿命性重复接近后,而被摧毁。孑遗下来的这些古天体,年龄高于地球化石与其他任何的银河结构体,也为宇宙的年龄提供了下限值。因为条件不再,我们银河系后来几乎没再形成年轻球状星团。这部主题影片,呈现了从地球到球状星团Terzan 5沿途上的可能景观,最后并以哈伯太空望远镜拍摄的一幅此星团照片终结。在此星团之内,最近发现除了有形成于银河系早期的恒星之外,并且很意外的还有在银河系诞生后大约70亿年一波恒星形成暴时,所形成的恒星。
翻译:“每日一天文图”成大物理分站

Zooming in on Star Cluster Terzan 5
Image Credit & Copyright: Nick Risinger (skysurvey.org), DSS, Hubble, NASA, ESA, ESO; Music: Johan B. Monell

Explanation: Globular clusters once ruled the Milky Way. Back in the old days, back when our Galaxy first formed, perhaps thousands of globular clusters roamed our Galaxy. Today, there are less than 200 left. Over the eons, many globular clusters were destroyed by repeated fateful encounters with each other or the Galactic center. Surviving relics are older than any Earth fossil, older than any other structures in our Galaxy, and limit the universe itself in raw age. There are few, if any, young globular clusters in our Milky Way Galaxy because conditions are not ripe for more to form. The featured video shows what it might look like to go from the Earth to the globular cluster Terzan 5, ending with a picture of the cluster taken with the Hubble Space Telescope. This star cluster has been found to contain not only stars formed in the early days of our Milky Way Galaxy, but also, quite surprisingly, others that formed in a separate burst of star formation about 7 billion years later.
Astronomy Picture of the Day 03/24/2019