Time series of satellite mass distribution for Disk1 [M_disk = 3M_tot, q = 1.50]. The red filled circles represent grown-up particles in this simulation, and the lines from their centers to both sides have a length of 5r_H. The blue stars represent Ariel, Umbriel, Titania, and Oberon in the current satellite system. The dashed lines indicate the Uranian radius and the solid lines indicate the isolation mass distribution for the initial disk: 2.5 × 10⁶T_K equals ∼3100 yr.