HF Doppler probing the disturbances originating in the ionosphere from natural and anthropogenic sources

Measurements were made in 1995 to 2000 at the two frequencies of 2.8 MHz and 3.0 MHz. The moving solar terminator generated detectable effects only in the absence of other disturbances in the ionosphere, and, most of all, in the absence of magnetic storms. The response to the dawn terminator commenced immediately after sunrise in the lower part of the ionospheric F-region where the probing radio waves are reflected. HF Doppler radar investigations of a variety of processes associated with rocket launches were performed over the same period of time. The observations have been analysed of thirty two launches from different cosmodromes (Baikonur, Plesetsk, Cape Canaveral, Kourou, and others).