Most distant oxygen ever observed

A team of astronomers has used the Atacama Large Millimeter/submillimeter Array (ALMA) to detect glowing oxygen in a distant galaxy seen just 700 million years after the Big Bang. This is the most distant galaxy in which oxygen has ever been unambiguously detected, and it is most likely being ionized by powerful radiation from young giant stars. This galaxy could be an example of one type of source responsible for cosmic reionization in the early history of the Universe.