Astroboffins find most distant source of oxygen in the universe

13 billion light years away, so no chance to have a huff

galaxy_impression
Artist's impression of an ancient, young galaxy. Image credit : NRAO/AUI/NSF; S. Dagnello

Astrophysicists have detected the most distant signal of oxygen yet, in a galaxy more than 13 billion light years away, when the universe was less than 4 per cent of its current age.

A paper published in Nature shows that the galaxy, MACS1149-JD1, was surprisingly mature enough to be forming abundant amounts oxygen at such a young age.

“This extremely distant, extremely young galaxy has a remarkable chemical maturity to it. It is truly remarkable that ALMA detected an emission line – the fingerprint of a particular element – at such a record-breaking distance,” said Wei Zheng, co-author of the paper and an astronomer at Johns Hopkins University.

The team found the telltale oxygen signal using the Atacama Large Millimeter/submilliter Array (ALMA) telescope. As the atoms were blasted away into space from a supernova burst, the energy heated them up until its electrons boiled away.

These ionised oxygen atoms emitted infrared energy. As these light waves travelled through space, they got stretched as the universe expanded and the wavelength increased to millimeter-wavelength light that is detectable with ALMA.

We are star dust

Complex elements are forged during the star formation process, firing up temperatures hot enough for nuclear fusion to take place. First, the lightest elements like helium and lithium are made. Next, further reactions produce carbon, nitrogen, and oxygen.

The team estimate that the galaxy had to be forging stars just some 250 million years after the Big Bang. At the beginning, the universe started as a hot primordial soup of quarks and gluons. These combined to form particles like protons, neutrons, electrons to build atoms.

Uranus

Astroboffins discover the stink of eggy farts wafting from Uranus

READ MORE

It takes several life cycles of the birth and death of stars to generate detectable amount of elements like oxygen, where they are scattered throughout space through powerful supernovae explosions. It is believed that the oxygen detected was from the second generation of stars in the galaxy, 500 million years after the Big Bang.

It’s not the first time that ALMA has found distant sources of oxygen: The record has been broken many times. In 2016, a team led by Akio Inoue, co-author of the paper and an associate physics professor at Osaka Sangyo University, spotted signs 13.1 billion light years. Months later, another team led by Nicholas Laporte, co-author of the paper and a research fellow at the University of College London, found oxygen at 13.2 billion light years.

For the new study, both teams collaborated to discover the signal at 13.28 billion light years - the furthest distance yet.

“With this discovery we managed to reach the earliest phase of cosmic star formation history. We are eager to find oxygen in even farther parts of the universe and expand the horizon of human knowledge,” said Takuya Hashimoto, first author of the paper and a postdoctoral researcher at the Osaka Sangyo University.

Finding such distant sources could help astronomers explore the first generation of stars and galaxies and help scientists piece together the history of the universe. ®




Biting the hand that feeds IT © 1998–2018