Astronomers have determined that an ancient star cluster called Terzan 5 is a potential fossilized galactic relic that has been frozen in time. This primordial star cluster can also shed new light about the evolution of the Milky Way galaxy.
Terzan 5 has already been known to scientists for quite some time now, however, new observations reveal unprecedented detail that confirms the cluster's ancient properties. Located 19,000 light years away in the constellation Sagittarius, new data was obtained using the European Southern Observatory's Very Large Telescope.
New imagery reveals that Terzan 5 possesses two distinct sets of stars with different ages and chemical signatures. New evidence is also suggesting that these globular clusters experienced two stages of stellar activity separated by 7 billion years.
Current models of the Milky Way reveals complex formations, starting from a slow and steady accretion of gas and dust, forming into smaller stars. Mini halos form around these stars as they merge with each other over time, as the oldest stars huddle in the core bulge in the center of Milky Way. Younger stars can be found lying around the outskirts of the galaxy.
A peek inside Terzan 5's stellar composition reveals similar features to the ones found in the central disc of the Milky Way. This new evidence suggests that this star cluster might be one our galaxy's earliest building blocks, however, it could have failed to merge with its other neighboring star systems, ultimately becoming frozen in time.
According to lead author of the study, Francesco Ferraro of the University of Bologna, some of the remnants found inside these gaseous clumps probably remained untouched, without any disturbances through time and just existed while being embedded inside the galaxy. These galactic fossils is also deemed crucial for astronomers to reconstruct important parts of the Milky Way.
This new study is published in the Astrophysical Journal.