Understanding Billions of Daily Meteor Impacts using Plasma Physics

Lars Dyrud

Center for Remote Sensing, Inc.

Every day, billions of meteoroids impact and disintegrate in the Earth's atmosphere. Current estimates for this global meteor flux vary from 2000-200,000 tons per year, and estimates for the average velocity range between 10 km/s to 70 km/s. The basic properties of this global meteor flux, such as the average mass, velocity, and chemical composition remain poorly constrained. We believe much of the mystery surrounding the basic parameters of the interplanetary meteoroid flux exists for the following reason, the unknown sampling characteristics of different radar meteor observation techniques, which are used to derive or constrain most models. We believe this arises due to poorly understood radio scattering characteristics of the meteor plasma, especially in light of recent work showing that plasma turbulence and instability greatly influences meteor trail properties at every stage of evolution. This seminar will present plasma simulations of various stages of meteor trail evolution together with radar observations of such trails. Model and observation comparisons indicate the ability to understand meteor trail, atmospheric, and meteoroid properties in a more detailed manner then previously achieved.