Scientists have long reckoned that the first galaxies came into being
roughly 500 million to 1 billion years after the Big Bang, but finding
these ancient celestial bodies is tricky when their light is so faint that even many specialized tools aren't up to the job. However, researchers have managed to spot
a galaxy so old that it's making them question the established timeline
for the universe. They've determined that the recently discovered
EGS8p7 galaxy is a whopping 13.2 billion years old, making it both the
farthest known galaxy to date and just 600 million years younger than
the universe as we know it. Theoretically, it shouldn't be possible to
see the galaxy at all -- in EGS8p7's era, space was supposed to be full
of neutral hydrogen clouds that absorbed radiation and made galaxies
invisible to later observers.
The discoverers have some theories for why they found this
extremely distant star hub. The hydrogen reionization in its era may
have been patchy, making it feasible to spot some galaxies but not
others. Also, EGS8p7 may have been populated by exceptionally hot stars
that created a giant hydrogen bubble and broadcast the galaxy's
presence. Whatever factors led to this rare sighting, it's clear that
humanity's understanding of the oldest galaxies still needs some
fine-tuning.
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