Time difference between our hybrid simulations and the location of the magnetospheric boundary crossings during the M1 flyby obtained from MESSENGER magnetic field observations by Slavin et al. (2008). The dashed lineis a linear fit of our results using an ordinary least-squares fitting function. Panels a and b: inbound bow shockand magnetopause crossings. Panels c and d: outbound magnetopause and bow shock crossings. P_dyn = is the solar wind dynamic pressure and M_A = is the Alfvén Mach number.