Cumulative number of craters per square kilometer as a function of crater diameter D for Janus and Epimetheus. Solid lines refer to our model calculated for both values of the impactor size distribution index (top lines are for s₂ = 3.5 and bottom lines for s₂ = 2.5) and color points represent the observations presented in Plescia & Boyce (1985) and Thomas et al. (2013). Dashed vertical lines indicate the strength-to-gravity transition crater diameter D_l on each satellite and solid vertical lines indicate the mean body diameter D_s of each satellite.