Distance as a Function of Redshift for Small Redshifts

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Distance versus $z$ for $z \ll 1$

If $z \ll 1$,
\[
d \sim \frac{cz}{H_{0}} = \frac{4163.78 z}{h_{72}} \ {\rm Mpc} \ \ \ (H_{0} \equiv 72h_{72}).
\]
See cosmology section for $z$ not $\ll1$. Here $d$ is the distance in Megaparsecs (Mpc), and $H_{0}$ is the Hubble constant in units of ${\rm km \ s^{-1} \ Mpc^{-1}}$.