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 Howes.
Not only is Himiko very large, it is extraordinarily distant, seen at a time approximately 800 million years after the Big Bang, when the universe was only 6 percent of its present size and stars and galaxies were just beginning to form.
“Perhaps they ended their lives as hypernovae - poorly understood explosions of probably rapidly rotating stars producing 10 times as much energy as normal supernovae,” she said.
Project leader Martin Asplund, professor at ANU-RSAA said finding such rare relic stars among the billions of stars in the Milky Way centre was like finding a needle in a haystack.
Melbourne: Astronomers have discovered the oldest known stars near the centre of the Milky Way galaxy, dating back to the time when the universe was just 300 million years old.
The stars are surprisingly pure but contain material from an even earlier star, which died in an enormous explosion called hypernova, the researchers said.