# Distance as a Function of Redshift for Small Redshifts

### 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 ${\rm km \ s^{-1} \ Mpc^{-1}}$.