| Summary: | The paper presents data on long-lived (~20–40 min) meteor trails. We describe a group of soliton-type meteor trails expanding at transonic speeds. Radio sounding data evidences that the latter include ~7–8 min ionization trails. We also consider one event with an ordinary shape and dynamics of meteor trails. These ordinary meteor trails are formed due to wind flows at heights of meteor glow. We describe the space-time structure of the detected meteor trails. In particular, in the November 18, 2017 event the typical size of the expanding trail area reached approximately 400 km and retained its semioval shape. The meteor trail propagated mainly in the horizontal plane at heights of ~86–91 km. We examine possible mechanisms of long-lived meteor trails propagating at transonic speeds. We estimate speed variations of meteor particles of size from 1μm to 10 mm for ~70–120 km heights during their horizontal motion. It is shown that the mode of meteor particle motion without deceleration on the typical timescale of ~10 3 s at 70–90 km heights can be realized only for large particles over 100 μm. Mechanisms and spectral composition of long-lived meteor trail glow are discussed.
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