Redshift uncertainties (in magnitude units) due to different levels of peculiar velocities as a function of the cosmological redshift. The solid black line corresponds to the Coma cluster velocity dispersion; the dashed and dash-dotted lines correspond to 300 and 150 km s⁻¹, respectively. The red line shows the intrinsic dispersion of SNe Ia on the Hubble diagram found for the JLA sample (Betoule et al. 2014).