Surroundings of the Julia family on the proper semimajor axis a_p vs. proper inclination sinI_p plot. All asteroids with eccentricities e_p = 0.11–0.14 are shown. Symbol sizes are proportional to the logarithm of diameters D. Colors correspond to the geometric albedos: p_V < 0.07 is blue, p_V > 0.15 (brown and yellow, gray if unknown). The family is close to the 3/1 mean-motion resonance with Jupiter and there are several secular resonances between the J3/1 separatrix and the family (2.51 and 2.55 au). The libration center of the 3/1 mean-motion resonance with Jupiterand its approximate width is denoted by the vertical strip. Approximate positions of the secular resonances z₁ ≡ g − g₆ + s − s₆, z₂, and z₃ computed for the mean eccentricity e = 0.125 are plotted as dotted curves. The black dashed rectangle indicates the region where the Julia family is located and which is analyzed in detail in the present work. The region delimited by the gray rectangle (above the black one) was selected as a suitable background population. The large family at sin I_p < 0.27 is Maria. The largest asteroid in the neighborhood is (13) Egeria. Julia family members identified at the cutoff velocity v_cut = 80 m s⁻¹ are shown in orange. The family is mainly composed of small asteroids (D ∈ (1;2.5) km) and is well separated from background asteroids.