3 ms·
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 t
by simonh 5y ago
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.
- cygx 5y ago45.5 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.