Radiotomographic observations of the ionosphere electron density at the Spitsbergen Archipelago-Kola Peninsula-Karelia meridian

The first results on the reconstruction of two-dimensional ionosphere electron density by the method of satellite tomography in the area extended for about 1700 km from the subauroral ionosphere (Karelia) to the nearpolar cap zone (northwest of the Spitsbergen Archipelago) are analyzed. This experiment is unique in that the satellite-receiving apparatus was placed on a research ship in the Barents Sea, which separates the Kola Peninsula and the Spitsbergen Archipelago. The results obtained are evidence of a complex ionospheric structure in this region even under the quiet geophysical conditions of sunlight irradiation.