University of Virginia | Fariss Samarrai | 2017 Sep 22
[img3="The tiny star-forming galaxy, dubbed J0811+4730, is a proxy for primordial galaxies."]http://news.virginia.edu/sites/default/ ... left_2.jpg[/img3][hr][/hr]A recently discovered dwarf galaxy in the constellation Lynx may serve well as a proxy for better understanding the developing chemistry of the early universe, according to a research team that includes University of Virginia astronomers.
Their new finding, published in the journal Monthly Notices of the Royal Astronomical Society, shows that the oxygen level in the little galaxy is the lowest yet discovered in any star-forming galaxy, likely resembling early nascent galaxies.
Astronomers know that the first galaxies during their forming stages were chemically simple -- primarily made up of hydrogen and helium, elements made in the Big Bang during the first three minutes of the universe’s existence. Oxygen came later, as massive stars formed and made heavier and more complex elements by nuclear fusion in their interiors and also in their explosive deaths, ultimately creating a universe of countless oxygen-rich galaxies like our Milky Way.
The earliest oxygen-deficient galaxies are so far away and so faint as to be nearly undetectable, but relatively close-by star-forming dwarf galaxies, with very little oxygen like early galaxies, may be easier to detect and offer the same clues. Unfortunately, these nearby tiny galaxies with little oxygen, which currently produce many massive blue stars, are very rare. But if detected, they can offer valuable insights to how the first galaxies formed some 13 billion years ago, and therefore to the evolution of the early universe. ...
J0811+4730: The Most Metal-Poor Star-Forming Dwarf Galaxy Known - Y. I. Izotov et al
- arXiv.org > astro-ph > arXiv:1709.00202 > 01 Sep 2017 (v1), 23 Sep 2017 (v2)