Reaching back to 'cosmic dawn'
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Reaching back to 'cosmic dawn'

Astronomers have made the most distant ever detection of oxygen. They observed it in a galaxy of stars that existed just 500 million years after the Big Bang. But what is really fascinating is that this oxygen can only have been produced in an even older group of stars that would have dispersed it when they died and blew themselves apart. That means we could be witnessing the traces of events that occurred a mere 250 million years after the Big Bang. Prof Richard Ellis from University College London spoke with our science correspondent Jonathan Amos.

  • 17 May 2018