Oldest known stars found, formed even before the Milky Way,
Astronomers have found out the oldest known stars near the centre of the Milky Way galaxy. Scientists believe that these are among the oldest stars in the universe.
While detailing about their age, astronomers suggested that they were formed when the universe was probably merely 300 million years old.
It is rather surprising as to how the astronomers are making such claims as they are so far away from earth that we can merely make assumption about them and cannot say anything conclusively.
â€œThese pristine stars are among the oldest surviving stars in the universe, and certainly the oldest stars we have ever seen,â€ said lead author Louise Howes, a PhD student at the Australian National University (ANU) Research School of Astronomy and Astrophysics. â€œThese stars formed before the Milky Way, and the galaxy formed around them,â€ said Howes. The discovery and analysis of the nine pure stars challenges current theories about the environment of the early universe from which these stars formed.
Howes says, â€œThe stars have surprisingly low levels of carbon, iron and other heavy elements, which suggests the first stars might not have exploded as normal supernovaeâ€¦Perhaps they ended their lives as hypernovae â€“ poorly understood explosions of probably rapidly rotating stars producing 10 times as much energy as normal supernovae,â€ she said. Project leader Martin Asplund, professor at ANU Research School of Astronomy and Astrophysics said finding such rare relic stars among the billions of stars in the Milky Way centre was like finding a needle in a haystack.
While detailing it further Asplund says, â€œThe ANU SkyMapper telescope has a unique ability to detect the distinct colours of anaemic stars â€“ stars with little iron â€“ which has been vital for this searchâ€. Following the teamâ€™s discovery in 2014 of an extremely old star on the edge of the Milky Way, the team focused on the dense central parts of the galaxy, where stars formed even earlier.