Observational data from Gaia (in gray) showing the perioddiameter distribution for asteroids. As purple squares we show the distribution of the Hygeia family, and as green triangles we show the distribution of the Massalia family. The dashed red line is the fit line that identifies the gap (Zhou et al. 2025). Spin period values were calculated by Durech & Hanus (2023) and Cellino et al. (2024). The ages in the legend are the weighted average ages computed from Spoto et al. (2015).