Parts of Milky Way could be older than previously thought: study

The corner of our Milky Way could be billions of years older than previously thought, researchers discovered using the Gaia space telescope after observing some ancient stars near the Sun. 

The stars have been located unexpectedly closer to the Sun and were formed less than a billion years after the Big Bang, culminating in the fact that a part of the Milky Way is much older than previously thought, Live Science reported. 

The disk on which the Sun and most stars are located was previously thought to be 8 to 10 billion years old but peeking into the space through the Gaia telescope and further study, the scientists have found that some of the stars are 13 billion years old. 

Interestingly, researchers found the antiquity of the stars by studying the data collected by the European Space Agency’s Gaia spacecraft. The revelation was announced by the Leibniz Institute for Astrophysics Potsdam (AIP) in Germany on July 31. 

It has been approximated that the universe is around 13.8 billion years old and the presence of 13 billion-year-old stars found in the Milky Way indicates that they were created just a few hundred years after the universe came into being. 

"These ancient stars in the disc suggest that the formation of the Milky Way's thin disc began much earlier than previously believed, by about 4-5 billion years," Samir Nepal, the study's lead author and a doctoral candidate studying the Milky Way at AIP, stated as quoted by Live Science. 

For the new study, the scientists observed that there are more than 800,000 stars in the Milky Way and the entire galaxy is about 100,000 light-years wide. 

The group of researchers utilised machine learning to combine data and found that the majority of the stars in our galaxy are more than 10 billion years old and some were even more than 13 billion years old. 

"This study also highlights that our galaxy had an intense star formation at early epochs leading to very fast metal enrichment in the inner regions and the formation of the disc," Nepal said.