A team of astronomers from the M. Keck Observatory in Maunakea, Hawaii, have made an incredible discovery: it is a rare relic of the ancient universe, a “fossil cloud” of gas created at the time of the Big Bang.
This ancient remnant of the Big Bang, this piece of pure material from the early universe, could help researchers better understand how and why different types of stars and galaxies formed in the early universe.
The WM Keck Observatory telescope also found a quasar , an ultra-bright active galactic nucleus that emits a lot of energy, hiding behind the gas cloud. This cloud is a remarkable find because it has changed very little since its inception.
“Wherever we look, the gas in the universe is polluted by heavy elements from exploding star debris. But this particular cloud appears pristine, unpolluted by stars, even 1.5 billion years after the Big Bang, “said Fred Robert of Australia’s Swinburne University of Technology. of 1 / 10,000 of what we see in our Sun. This is extremely low. The most compelling explanation is that it is a true relic of the Big Bang, “he added.
Because the quasar behind the cloud is very bright, it illuminates the material it contains. This illumination allowed experts to see the spectral shadows of hydrogen in the gas cloud, and because it has not been contaminated, it is a splendid look at what the cloud looked like billions of years ago.
This is not the first time we have seen a ‘fossil gas cloud’
This is not the first Big Bang cloud remnant ever discovered. In 2011, researchers discovered two other “fossil clouds.”
“The first two were serendipitous discoveries, and we thought they were the tip of the iceberg. But nobody has discovered anything similar, they are clearly very rare and difficult to see. It’s great to finally discover one in a systematic way, “added astronomer John O’Meara, who discovered the first two fossil clouds together with his colleagues.
“It is now possible to inspect these fossil relics from the Big Bang,” the authors explain.
Studying these ancient clouds will give scientists a better idea of what the universe was like at the time of the Big Bang, potentially explaining how and why some gases in the early universe became certain stars and galaxies, and others did not.
Este trabajo se publicará en la revista Monthly Notices de la Royal Astronomical Society.
Referencia: Monthly Notices of the Royal Astronomical Society. A preprint of the paper, “Exploring the origins of a new, apparently metal-free gas cloud at z = 4.4,” http://arxiv.org/abs/1812.05098.
Crédito imagen: TNG COLLABORATION
