Ancient gas cloud may be a relic from the death of first stars—8 January 2016

Researchers from Swinburne University of Technology (supported through the ARC Discovery Projects scheme) and the USA have discovered a distant, ancient cloud of gas that may contain the signature of the very first stars that formed in the Universe. The gas cloud has an extremely small percentage of heavy elements, such as carbon, oxygen and iron—less than one thousandth the fraction observed in the Sun. It is many billions of light years away from Earth, and is observed as it was just 1.8 billion years after the Big Bang. The observations were made by the Very Large Telescope in Chile. “Heavy elements weren't manufactured during the Big Bang, they were made later by stars,” said lead researcher, Dr Neil Crighton, from Swinburne University of Technology’s Centre for Astrophysics and Supercomputing. “The first stars were made from completely pristine gas, and astronomers think they formed quite differently from stars today.” Co-author, Swinburne’s Professor Michael Murphy, said “This is the first cloud to show the tiny heavy element fraction expected for a cloud enriched only by the first stars.”

The paper will be published in the Monthly Notices of the Royal Astronomical Society Letters on 13 Jan 2016, and is also available as a pre-print.

Media issued by Swinburne University of Technology.

Image: A simulation of the first stars in the Universe, showing how the gas cloud might have become enriched with heavy elements. 
Image credit:  Britton Smith, John Wise, Brian O'Shea, Michael Norman, and Sadegh Khochfar. For more information visit Dr Britton Smith’s website.

Original Published Date: 
Friday, January 8, 2016