Normalized radial profile of C/2018 F4 (PANSTARRS) in the image shown in Fig. 1 (in red) compared to that of a field star (in black). The Moffat profile of a point-like source (solid line in green) with the FWHM of the stars in the images, and the corresponding profile of an extended object (solid line in black) with a 1∕ρ profile (the profile of an isotropic dust coma) are shown. The solid line in blue is the 50:50 linear combination of the point-like source (nucleus) and 1∕ρ profile (dust coma). The similarity of the combined profile to the observed one suggests that the nucleus contributes significantly to the overall brightness of the comet.