Top panel: distance between IC 1396A and HD 206267 as a function of the current angle with respect to the line of sight (β_t=0). Bottom panel: minimum distance between IC 1396A and HD 206267 (blue) and time at which the minimum distance was reached (green) as a function of the current angle with respect to the line of sight (β_t=0). The time isgiven in Myr, with the current time set at 0 Myr, which makes all quantities negative. The velocity is considered constant and equal to the velocity observed in the plane of the sky and radial directions, which is a good approximation for the past 2–1.5 Myr (see text). The distances at which the ionizing photon flux is equal to 1e9 and 1e10 cm⁻² s⁻¹ are shown as horizontal dotted and dashed lines, respectively.