Graphic of the R Aqr system near mid-eclipse viewed from the side. The system is inclined 18° to the line of sight. The hatched rectangle is the nominal 5 au radius accretion disk with h/r = 0.2. The orange disk labeled “Mira” illustrates the approximate 2 au radius of the Mira’s IR photosphere. The approximate shape of the Roche potential is illustrated using the Eggleton (1983) radius (heavy dashed line). The potential is shown extended to the inner Lagrange point, L₁. The Roche radius of the Mira at periastron is ∼4.9 au and of the WD ∼4.0 au. L₁ is ∼6.4 au from the center of the Mira (Plavec & Kratochvil 1964) and the Mira is clearly detached. Eclipse is near periastron when the WD Roche lobe is smaller than the nominal accretion disk. At apastron the WD Roche radius is ∼6.6 au. The approximate regions observed in CO emission and absorption are marked.