Astronomers have detected oxygen in a 13-billion-year-old galaxy — the first time that the gas has been found at such an early stage of the Universe.
A team led by Akio Inoue at Osaka Sangyo University in Daito, Japan, used the powerful Atacama Large Millimeter/submillimeter Array (ALMA) in Chile to measure the chemical make-up of the galaxy, which was discovered in 2012. Oxygen was only one-tenth as abundant as it is in the Sun, and the galaxy seemed to be low in neutral gas and dust.
Such characteristics may have allowed ultraviolet light from the stars of this and other similar galaxies to escape and ionize the hydrogen atoms in the early Universe, eventually generating the levels of ions seen today.
Science http://doi.org/bj5z (2016)