
Milky Way’s ancient core revealed: Terzan 5 as a bulge fossil fragment
NASA’s JWST and Hubble visualisation traces Terzan 5, a dense stellar system in the Milky Way’s bulge about 22,000 light-years away in Sagittarius. Once thought a simple globular cluster, Terzan 5 is now seen as a bulge fossil fragment hosting four star generations, with some stars dating back ~12.5 billion years, and a mass of about two million solar masses. Its survival offers clues to the early Milky Way’s formation as the bulge assembled.

