Oldest stars found near Milky Way centre »

Astronomers have discovered the oldest known stars, dating from before the Milky Way Galaxy formed, when the Universe was just 300 million years old. The stars, found near the centre of the Milky Way, are surprisingly pure but contain material from an even earlier star, which died in an enormous explosion called a hypernova. "These pristine stars are among the oldest surviving stars in the Universe, and certainly the oldest stars we have ever seen," said Louise Howes, lead author of the study published . "These stars formed before the Milky Way, and the galaxy formed around them," said Ms Howes, a PhD student at the ANU Research School of Astronomy and Astrophysics. The discovery and analysis of the nine pure stars challenges current theories about the environment of the early Universe from which these stars formed. "The stars have surprisingly low levels of carbon, iron and other heavy elements, which suggests the first stars might not have exploded as normal supernovae," said Ms Howes. "Perhaps they ended their lives as hypernovae - poorly understood explosions of probably rapidly rotating stars producing 10 times as much energy as normal supernovae." Project leader Professor Martin Asplund, from ANU Research School of Astronomy and Astrophysics said finding such rare relic stars amongst the billions of stars in the Milky Way centre was like finding a needle in a haystack.