Globular clusters near the Milky Way's center are difficult to observe. But the Hubble is able to, and we're lucky for that.
The program gave us great images of these clusters and has led to a number of papers examining GCs near the Milky Way’s center.
The NASA/ESA Hubble Space Telescope imaged the globular star cluster Djorgovski 1, which was only discovered in 1987. Djorgovski 1 is located close to the centre of our Milky Way Galaxy, within the bulge. Globular clusters like Djorgovski 1 formed early in the Milky Way’s history, and as such, may hold clues about the inner galaxy’s early evolution. Image Credit: By ESA/Hubble & NASA – http://www.spacetelescope.org/images/potw1126a/, CC BY 3.0, https://commons.wikimedia.org/w/index.
showed that Palomar 6 shares the same metallicity as some other GCs in the region, including M62. That paper concluded that Palomar 6 is about 12.5 billion years old and probably formed in the bulge in the Milky Way’s early days, along with several other GCs.