This article presents a summary of various luminous phenomena that may follow after passage of a meteor. The terminology recommended by the International Astronomical Union in 1961 is used, which calls these phenomena trains. Nowadays, several types of trains can be clearly distinguished. The understanding of the underlying physical and chemical processes is, however, still not satisfactory and the nomenclature of different train phenomena has not yet been settled. In this paper I call them wake, green train, persistent train, and reflection train. Meteor wakes are formed by rarified non-equilibrium gas behind the meteoroid. The green train, produced by the radiation of the forbidden oxygen line at 557.7 nm, is created by reactions among atmospheric species. The persistent train is the most complex phenomenon with three phases of evolution. The afterglow phase is formed by cooling rarified gas. After that, atomic recombination phase follows. The third and most persistent continuum phase is probably fed by chemiluminescence. Finally, the reflection train occurs when sunlight is scattered by a dust cloud created by meteoroid disruption.
Journal of the Royal Astronomical Society of Canada
- Pub Date:
- October 2006