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Title: James Webb Space Telescope Discovers the Earliest Galaxy Ever Seen

Link: https://science.slashdot.org/story/25/06/04/0...

The James Webb Space Telescope has discovered the most distant galaxy ever
observed, named MoM z14. NASA estimates it existed just 280 million years
after the Big Bang. Space.com reports: Prior to the discovery of MoM z14, the
galaxy holding the title of earliest and distant was JADES-GS-z14-0, which
existed just 300 million years after the Big Bang, or around 13.5 billion
years ago. This previous record galaxy has a redshift of z =14.32, while MoM
z14 has a redshift of z = 14.44. There is a wider context to the observation
of MoM z14 than the fact that it has broken the record for earliest known
galaxy by 20 million years, though, as [explained team member and Yale
University professor of Astronomy and Physics Pieter van Dokkum]. The
researchers were able to determine that MoM z14 is around 50 times smaller
than the Milky Way. The team also measured emission lines from the galaxy,
indicating the presence of elements like nitrogen and carbon. "The emission
lines are unusual; it indicates that the galaxy is very young, with a rapidly
increasing rate of forming new stars," van Dokkum said. "There are also
indications that there is not much neutral hydrogen gas surrounding the
galaxy, which would be surprising: the very early universe is expected to be
filled with neutral hydrogen. "That needs even better spectra and more
galaxies, to investigate more fully." The presence of carbon and nitrogen in
MoM z14 indicates that there are earlier galaxies to be discovered than this
13.52 billion-year-old example. That is because the very earliest galaxies in
the universe and their stars were filled with the simplest elements in the
cosmos, hydrogen and helium. Later galaxies would be populated by these
heavier elements, which astronomers somewhat confusingly call "metal," as
their stars forged them and then dispersed them in supernova explosions. The
research has been published on arXiv.

Read more of this story at Slashdot.

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