Investigation of shock waves and tangential discontinuities of the cosmic plasma by the radio interference technique

The possibility of investigation of the cosmic plasma dynamics by the radio interference technique based on a finite time of radio wave propagation between the sounding and responding stations is shown. By locating the sounding station on a spacecraft the greatest contribution to the phase difference ΔΦ(t)or the phase difference growth rate $\text{Δ?}$ between the sounding and response signals are caused by disturbances in close proximity to the spacecraft. This method permits interplanetary shock waves and tangential discontinuities to be registered and the velocities and plasma density changes on their fronts to be determined. By using experimental data of ΔΦ(t) or $\text{Δ?(t)}$ one can also obtain information about plasma concentration jump, location and motion of bow shock wave and magnetopause and plasmapause. Available experimental data about different disturbances of cosmic plasma were analysed and the requirements on frequency stability of spacecraft-borne and groundbased radio equipment were estimated to register those disturbances. In most cases relative stability 10^?11–10^?13 provided by present atomic frequency standards is sufficient.