星团

Hubble was able to resolve six variable stars in M31.

哈勃望远镜能分辨梅西叶星云星团表31中的六颗变星。

We also describe the basic principle of white dwarf cosmochronology and its application in defining the age of the Galactic disk, globular clusters, open clusters and Galactic halo.

白矮星宇宙纪年学研究的基本原理及其在银盘、球星团、疏散星团及银晕年龄确定方面的应用现。