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A comment on Astronomers just discovered the farthest object in the known universe. Parent comment

Re:Astronomers just discovered the farthest object in the kn... by cygx on Friday April 08, 2022 @06:37PM (#30963355)
What are you basing the 45 bn ly on? A redshift of z~13 should correspond to a comoving distance of about 33 bn ly, whereas 45 bn ly would correspond to z~600.
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Re:Astronomers just discovered the farthest object in the kn... by simonh on Saturday April 09, 2022 @02:25AM (#30965675)
You may be right, I've just seen ~45 bn ly given as the radius of the observable universe accounting for expansion. The discrepancy could be due to changes in the rate of expansion over time, as it hasn't been constant.
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Re:Astronomers just discovered the farthest object in the kn... by cygx on Saturday April 09, 2022 @05:22AM (#30966454)
45.5 bn ly is the approximate comoving distance of the surface of last scattering (the source of the microwave background and the point where the universe becomes opaque). This is the boundary of the universe observable via electromagnetic radiation.
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