New distance of HMSC (this work) and those in Y17. Panel a: distance difference Δ_D = D_new − D_Y17. The red dashed lines show |Δ_D| = 0.8 kpc, representing the 70th percentile of |Δ_D|. The red,blue, orange, green, and purple dots mean that their KDA are solved by IR dark, H I SA, tangent, scale height, and literature, respectively (see Table 4 and Appendix A). The black dots are the sources without KDA solution. Panel b: |Δ_D | and its relation with the difference between resulted far distance and near distance D_far − D_near. Only HMSCs with |Δ_D| > 0.8 kpc and km s⁻¹ are shown. The gray region shows (D_far − D_near)∕|Δ_D| = 1 ± 0.8∕|Δ_D|, indicating the error of relation. The gray cross shows the typical error.