Terzan-5
Terzan-5 is star cluster, with an estimated mass two million times the mass of Sol, our sun.[1] The entire cluster is only a few tens of lightyears in diameter.[2]
It was discovered in 1968 by Astronomer Agop Terzan, in the constellation Sagitarius.[1] It is located 22,000 lightyears away, in the bulge at the centre of our galaxy, The Milky Way.[2]
Terzan-5 was originally classified as a globular cluster, and believed to be made of stars that all formed at the same time and place, but, in 2009, it was reclassified as a bulge fossil fragment, because it contains four populations of stars, created in four separate times.[1][2]
References
[edit | edit source]- ↑ 1.0 1.1 1.2 Anton Petrov (2026-06-24). "Globular Cluster in the Milky Way Turned Out To Be Something Different". What da Math – via YouTube.
- ↑ 2.0 2.1 2.2
"Bulge Fossil Fragment Terzan 5". NASA Science. 2026-06-16. Archived from the original on 2026-06-24. Retrieved 2026-06-24.
This finding proved that Terzan 5 is not a globular star cluster, as originally classified. Instead, Terzan 5 belongs to a new category, known as a bulge fossil fragment — a self-contained, self-enriching stellar system with multiple star populations of different ages and with different iron abundances.