RUSSIAN JOURNAL OF EARTH SCIENCES, VOL. 20, ES6009, doi:10.2205/2020ES000748, 2020
B. G. Gavrilov, V. A. Pilipenko, Y. V. Poklad, I. A. Ryakhovsky
Possibilities of studies of the geomagnetic effects produced by the interaction of a cosmic bodies with the magnetosphere-ionosphere-atmosphere system are very limited due to extremely small number of examined events. Here we present geomagnetic observations at an array of magnetometers during Bering Sea Bolide event on December 18, 2018 when a space body entered the Earth's atmosphere and exploded at the altitude of $\sim 25$ km near Kamchatka. It has been found that the short-lived electromagnetic signal appeared before the explosion and, consequently, was trigged by the passage of a meteoroid through the inner magnetosphere. Geomagnetic disturbances of the same duration and frequency of oscillations were detected both in the area adjacent to the explosion site in the Northern hemisphere and in the magnetically conjugated area in the Southern hemisphere. These observations may be provisionally interpreted as a triggered excitation of resonant field line oscillations in the inner magnetosphere by the fast-moving meteoroid. The magnetosphere is often in a metastable state, when even a weak external trigger can stimulate an internal instability and wave generation. The appearance of a diamagnetic effect during partial ablation of a meteoroid could cause a local disturbance of the geomagnetic field and its propagation in the magnetic force tube.
Received 07 August 2020; accepted 06 November 2020; published 24 November 2020.
Citation: Gavrilov B. G., V. A. Pilipenko, Y. V. Poklad, I. A. Ryakhovsky (2020), Geomagnetic effect of the Bering Sea meteoroid, Russ. J. Earth Sci., 20, ES6009, doi:10.2205/2020ES000748.
Copyright 2020 by the Geophysical Center RAS.