GS-9209 is a massive Quiescent galaxy quiescent galaxy: a galaxy that is no longer forming stars located in the constellation Fornax at a redshift of 4.658 or at a comoving distance of 25 billion light years. It has a stellar mass of which is roughly 10 times the mass of the Milky Way galaxy.
When the universe was around 800 million years old, the star formation rate (SFR) in the GS-9209 galaxy has undergone a sharp decrease. Most of the stars that exist in this galaxy have formed over a 200 million year period when the universe was 600-800 million years old.
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