M15: 紧实的球状星团
2023年6月15日 M15: Dense Globular Star Cluster Image Credit: NASA, ESA, Hubble Legacy Archive; Processing: Ehsan Ebrahimian Explanation: Messier 15 is an immense swarm of over 100,000 stars. A 13 billion year old relic of the early formative years of our galaxy it’s one of about 170 globular star clusters that still roam the halo of the Milky Way. Centere...