Early Star Formation Presents New Cosmic Mystery:
New observations suggest that stars began forming just 250 million years after the Big Bang — a record-breaker that will likely open a new line of cosmological inquiry.
Astronomers peering back into time suggest that the cosmic dark ages — before the universe hosted its sea of twinkling lights — might have lasted no more than 250 million years. The team presented their results in the journal Nature [DOI: 10.1038/s41586-018-0117-z] [DX] today.
Takuya Hashimoto (Osaka Sangyo University, Japan) and his colleagues used the Atacama Large Millimeter/submillimeter Array (ALMA) to peer at a galaxy whose light was emitted 550 million years after the big bang, picking up a long-sought signal: oxygen. It's the most distant galaxy for which astronomers have been able to detect individual elements — and that single element has a big story to tell.
Because only hydrogen, helium, and a little lithium emerged from the Big Bang, the young universe was pristine. It wasn't until the first generation of stars exploded, breathing carbon, oxygen and other heavy elements into the cosmos, that the universe's inventory of elements increased. So, the detection of oxygen 550 million years after the Big Bang suggests that a generation of stars had already formed and died by this point.
Also at the National Radio Astronomy Observatory.
Submitted via IRC for Runaway1956
Scientists have spotted an oxygen signal deep in the universe, suggesting it formed far differently from how we thought. The new discovery is the most distant oxygen ever seen by a telescope. And it could change our understanding of how stars and the universe as we know it came about. The galaxy is so far away that we are seeing it as it was when the universe was only 500 million years away[sic. And even at that age, it is filled with mature stars – suggesting the process of their formation began only 250 million years after the universe itself began.
(Score: 3, Informative) by tizan on Friday May 18 2018, @04:44PM
From wikipedia:
https://en.wikipedia.org/wiki/Big_Bang_nucleosynthesis [wikipedia.org]
Quote:
Big Bang nucleosynthesis produced very few nuclei of elements heavier than lithium due to a bottleneck: the absence of a stable nucleus with 8 or 5 nucleons. This deficit of larger atoms also limited the amounts of lithium-7 produced during BBN. In stars, the bottleneck is passed by triple collisions of helium-4 nuclei, producing carbon (the triple-alpha process). However, this process is very slow and requires much higher densities, taking tens of thousands of years to convert a significant amount of helium to carbon in stars, and therefore it made a negligible contribution in the minutes following the Big Bang