Modeling long duration meteor trails

Abstract

We constructed a model of the plasma evolution of meteor trails in order to simulate high‐power‐large‐aperture radar observations. This model follows meteor evolution from ablation and ionization to head echo formation and through non‐specular trail reflections. Meteor plasma field aligned irregularities (FAI) result in radar reflections called non‐specular meteor trails. We have updated our model to include the polarizing effects of winds and background electric fields on meteor trail instability. This model incorporates existing meteor physics together with knowledge we gained from the simulations, such as instability physics and anomalous diffusion. Comparing results from this model with large radar observations of head echoes and non‐specular trails shows that we can reproduce many of the observed features, such as the detailed altitude profile and duration of head echoes and non‐specular trails. Specifically when external electric fields are included in our model, the same model predicts both short duration (order of 1 s) and long duration meteor trails (several minutes) depending upon the characteristics of the meteoroid and atmosphere. The addition of a background E‐field or wind also reproduces a commonly observed non‐specular trail feature we call an “extended tail” where the delay time between head echo and non‐specular reflection at the lower altitude portion of the trail increases as the meteor gets lower in the atmosphere. We also demonstrate a dependence on trail duration with the electron density of the background ionosphere.