Physical parameters measured by PSP and Solar Orbiter around the predicted plasma line-up. The proton density N_p is shown in panels a and c, and B, the magnitude of the magnetic field is shown in panels b and d. Blue curves (panels a and b) are PSP measurements around t_in, and oranges curves (panels c and d) are Solar Orbiter measurements around t_out, when the minimum distance d_MIN is achieved. Density structures are indicated between two vertical dashed lines, for t ∈ [ − 0.5, 1.5] h and for t ∈ [137, 139] h, in PSP and Solar Orbiter measurements, respectively.