Milky Way
Globular
Clusters
Index
1. Introduction
2. Orbits
3. Omega Centauri
4. 47 Tucanae
5. 47 Tuc Core
6. 47 Tuc Blue Stragglers
7. M4
8. M5
9. M10
10. M13
11. M15
12. M22
13. NGC 6522
14. Galactic Centre Chart
15. List of MW Globulars
16. Credits and Links
M5
Image credit: Robert J Vanderbei
M5 or NGC 5904 is in constellation Serpens. It is just visible to the naked eye (visual magnitude of 5.6). In 1783, William Herschel resolved its brighter stars - with his better instruments, he was able to resolve the stars of all the globular clusters in Messier's catalog. Its brightest stars are of apparent magnitude 12.2. It is about 24,500 light-years away from Earth. It contains somewhere between 100,000 and 500,000 stars. At 165 light-years across, is one of the more extended globular clusters. At 13 billion years old it is also one of the older Milky Way globulars.
Sources:
Messier 5 - Wikipedia
Messier 5, observations and descriptions - SEDS