Schematics of the shock wave fit. The parameters displayed are those of the ellipsoid model: r (blue dashed line) represents the distance between the surface of the Sun and the centre of the ellipsoid; a, b, and c (green dashed lines) are the half-axes; V_R and V_L (red line) represent its radial and lateral speeds, respectively. The shock wave is represented by a half-sphere for illustrative purposes, i.e. a(t)≈b(t)≈c(t) between 2 and 25 solar radii, which confirms the cone model.