Distances of the binary HD 4552,BD+120090. Left: contours of ${\chi }_{\mathrm{D}}^2=1,2,3,4$ (dotted lines) in the D₁, D₂ plane. The black and blue crosses show the Gaia and best-fitting distances, respectively. The dashed black line shows $D_{\mathrm{m}\mathrm{e}\mathrm{a}\mathrm{n}}={\overline{D}}_{\mathrm{m}\mathrm{e}\mathrm{a}\mathrm{n}}$; the green line shows D₁ = D₂. The blue and red dashed lines show distances delivering r = 2GM/V_tot². The blue and red dots show the first 100 D₁ and D₂ distances (ranked by ${\chi }_{\mathrm{D}}^2$) with v_max/V_tot ≤ 1. Right: probability distributions of the distances of HD 4552 (blue) and BD+120090 (red). The crosses show the best-fitting Newtonian solution. The dotted black and green lines show ${\overline{D}}_{\mathrm{m}\mathrm{e}\mathrm{a}\mathrm{n}}=(\overline{D_1}+\overline{D_2})/2$, respectively.