Toomre diagram for all the stars in the MMR group, in terms of the solar velocity, 232.8 km s⁻¹ (McMillan 2017). All velocities are median velocities extracted from GALPY as discussed in Sect. 2. Additionally, all velocities were corrected for the Sun’s velocities {U_⊙, V_⊙, W_⊙} = {8.6±0.9, 13.9±1.0, 7.1±1.0} as estimated by McMillan (2017 their Table 2). The dashed curves indicate the total space velocity in concentric steps of 50 km s⁻¹, which is represented as v_tot = (U² + V² + W²)^1/2. The uncertainties shown in this figure have been estimated via propagation of uncertainties.