Observations of persistent Leonid meteor trails: 4. Buoyant rise/vortex formation as mechanism for creation of parallel meteor train pairs

Abstract

In this paper we present numerical computations designed to demonstrate effects associated with the buoyant rise of persistent trails produced by large Leonid meteors in cases where the meteor velocity vector has a large horizontal component. We model the meteor trail as a hot cylindrical volume in an equilibrium atmosphere. The computed results show the hot cylinder first expanding radially and then rising because of buoyancy, while evolving into a pair of counterrotating linear vortices. These line vortex phenomena are offered as an explanation for the otherwise mysterious parallel pairs of trails that are often observed. We also show some high‐resolution images of double meteor trails observed during the high Leonid meteor activity of 1998–2002. For the case of the Diamond Ring event we compare computed and measured luminosity profiles for the sodium 589 nm emission and for the red–near IR O2 atmospheric band (O2(b1Σg+) – O2(X3Σg−)) emission.