From ABC Science News Online, 10 February 2014:
Astronomers have discovered the oldest known star, born in the fiery wake of a first generation supernova after the Big Bang.
The star, with the catchy name SMSS J031300.362670839.3, came to the attention of an international team of astronomers because of its unique chemical fingerprint showing it contained almost no iron.
The discovery is reported today in Nature.
Lead author Dr Stefan Keller says the first generation of stars that formed immediately after the big bang contained mostly hydrogen, helium and a small amount of lithium.
“They were made out of this very primordial mix of hydrogen and helium and that led them to become very massive stars, hundreds of times the mass of the Sun,” says Keller, who is a research fellow at the Research School of Astronomy and Astrophysics at the Australian National University.
“When you have a star that big, it lives fast and dies young. They explode in a supernova and they start to seed the rest of the universe.”
The resulting explosion contains heavier elements, such as carbon, silicon and iron.
“As soon as we’ve got a little bit of iron in the universe, that enables much smaller stars to form and that’s what we’re seeing in this finding — one of those stars from the second generation,” says Kellar. Read more.