Physics of Meteor Generated Shock Waves in the Earth's Atmosphere - A Review

TL;DR

This review comprehensively covers meteor-generated shock waves, focusing on their mechanisms, dynamics, and implications for planetary defense, highlighting current modeling challenges and detection methods like radar and infrasound.

Contribution

It provides an extensive synthesis of meteor shock wave phenomena, emphasizing the need for advanced models and detection techniques in meteor science and planetary defense.

Findings

Hydrodynamic shielding around meteoroids is crucial for shock wave formation.

Current models lack accuracy in describing shock waves of ablating meteoroids.

Radar and infrasound are key tools for studying meteor shock phenomena.

Abstract

Shock waves and the associated phenomena generated by strongly ablating meteoroids with sizes greater than a few millimeters in the lower transitional flow regime of the Earth's atmosphere are the least explored aspect of meteor science. In this paper, we present a comprehensive review of literature covering meteor generated shock wave phenomena, from the aspect of both meteor science and hypersonic gas dynamics. The primary emphasis of this review is placed on the mechanisms and dynamics of the meteor shock waves. We discuss key aspects of both shock generation and propagation, including the great importance of the hydrodynamic shielding that develops around the meteoroid. In addition to this in-depth review, the discussion is extended to an overview of meteoroid fragmentation, followed by airburst type events associated with large, deep penetrating meteoroids. This class of objects has a significant potential to cause extensive material damage and even human casualties on the ground, and as such is of great interest to the planetary defense community. To date, no comprehensive model exists that accurately describes the flow field and shock wave formation of a strongly ablating meteoroid in the non-continuum flow regime. Thus, we briefly present the current state of numerical models that describe the comparatively slower flow of air over non-ablating bodies in the rarefied regime. In respect to the elusive nature of meteor generated shock wave detection, we also discuss relevant aspects and applications of meteor radar and infrasound studies as tools that can be utilized to study meteor shock waves and related phenomena.