Panel (a): Eunomia family scatter plot, with asteroids colored based on their rotation periods. Panel (b): similar to panel (a) but in ﹩\delta -1/D﹩ space. Panel (c): variation of the mean period as a function of δ. Each data point corresponds to a Δδ = 0.1 bin. Panels (d), (e), and (f): as in (a), (b), and (c) but for the Hungaria family. Open points in panels (d) and (e) are asteroids with >20 hr periods.