Time evolution of X-ray (5–100 Å), EUV (100–920 Å), and total XUV luminosity of HD 63433, according to Penz et al. (2008) and the X-ray/EUV scaling by Sanz-Forcada et al. (2022). The grey area is the observed 1σ spread around the median (dark grey line) of the X-ray luminosity distributions for dG stars in the Hyades and Pleiades open clusters. Uncertainties on the age and X-ray luminosity of HD 63433 are within the size of the square symbol.