An Etymological Dictionary of Astronomy and Astrophysics

The → blackbody surface of the → Universe defined at a → redshift of about z ≥ 2 &times 10⁶. This is distinct from the → last scattering surface, in other words the → cosmic microwave background radiation (CMBR), which refers to z = 1100. Prior to the epoch of the blackbody photosphere
the distortions from the → Big Bang are exponentially suppressed.

See also: → blackbody; → atmosphere.