A new star family in the Milky Way's core was discovered by an astronomer from the Liverpool John Moores University, helping shed light on the beginnings of the galaxy.
Published in a paper in the Monthly Notices of the Royal Astronomical Society, the discovery was made through the Apache Point Observatory Galactic Evolution Experiment, which was carried out using the Sloan Digital Sky Survey. LJMU is one of the institutions participating in the SDSS, one of the most ambitious sky surveys in the history of astronomy.
New Star Family In The Milky Way
The new star family was spotted as the researchers performed infrared observations of the Milky Way's core. According to the researchers they were highly similar to stars seen inside globular clusters, which were formed as the galaxy was formed.
The researchers thought it was possible then that the new family of stars actually were previously part of globular clusters before they were destroyed as the Milky Way's core was formed. If this is so, globular clusters would be more numerous, about 10 times more their number in the galaxy's early years compared with their numbers today, pointing to the possibility that a significant portion of the old stars residing in the inner portions of the Milky Way may have come from globular clusters as well.
"This is a very exciting finding that helps us address fascinating questions such as what is the nature of the stars in the inner regions of the Milky Way, how globular clusters formed and what role they played in the formation of the early Milky Way," said Ricardo Schiavon, lead researcher for the project.
Observing The Milky Way
It's not always easy to observe the Milky Way, particularly the galaxy's core, because space dust is in the way. By making observations in infrared, APOGEE was able to take a closer look at the galaxy and see more clearly what is at the core of the Milky Way.
According to Schiavon, APOGEE made it possible for the researchers to identify the chemical makeup of stars in the thousands, from which a sizable number appeared to be different from the majority of stars in the Milky Way's inner regions because they had high levels of nitrogen.
The researchers are uncertain, but they suspect that the stars in question may have originated from the destruction of globular clusters at the time the galaxy was being formed. However, it is also possible that the stars they observed were byproducts of early star formation occurring as the Milky Way was formed. More studies will have to be conducted to test out their hypotheses.