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November twilight sounding experiments carried out in the Abastumani Astrophysical Observatory including the Leonid showers of 1998 and 1999 provided an opportunity to obtain height distributions of dust of meteoric origin between 20 km to 140 km altitudes. The formation of several dust layers and their subsequent descent and dissipation were observed during these periods. The layers at 117 km and 54 km were estimated to consist of particles of 0.01 µm and 21–23 µm radii respectively, according to settling velocities of these layers. The particle number density at 117 km altitude was estimated to be ∼30 p cm−3.