The first stars formed when the universe was less than 2% its current age
Astronomers have detected a 13.3-billion-year-old oxygen signal, which suggests the first stars began forming just 250 million years after the Big Bang.
By Jake Parks | Published: Wednesday, May 16, 2018
http://www.astronomy.com/news/2018/05/first-stars-from-oxygen (http://www.astronomy.com/news/2018/05/first-stars-from-oxygen)
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With the help of the Atacama large Millimeter/submillimeter Array, astronomers have detected the earliest signs of oxygen (red) distributed in the galaxy MACS1149-JD1. The discovery provides the strongest evidence yet that stars in the fledgling universe started forming earlier than previously thought — when it was less than 2 percent its current age.
ALMA (ESO/NAOJ/NRAO), NASA/ESA Hubble Space Telescope, W. Zheng (JHU), M. Postman (STScI), the CLASH Team, Hashimoto et al.
The Atacama Large Millimeter/submillimeter Array (ALMA) is not your standard, run-of-the-mill telescope. Instead, ALMA, which is located in the high-and-dry Atacama Desert of northern Chile, is a radio telescope made up of 66 high-precision antennas that operate in perfect harmony. When ALMA’s antennas (which range from 7 to 12 meters in diameter) are configured in different ways, the array is capable of zooming in on some of the most distant cosmic objects in the universe, as well as capturing images that are clearer than those produced by the Hubble Space Telescope.
First starlight
In a new study set for publication tomorrow in the journal Nature, an international team of astronomers used this impressive array to observe an extremely distant galaxy called MACS1149-JD1. Within the galaxy, the team was surprised to discover faint signals of ionized oxygen that were emitted almost 13.3 billion years ago (or 500 million years after the Big Bang).
This is not only the most distant detection of oxygen ever made by any telescope, but more importantly, the discovery of the ancient oxygen serves as clear evidence that stars began forming just 250 million years after the Big Bang, when the universe was less than 2 percent its current age.
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