Acoustic Signals of a Meteoroid Recorded on a Large‐N Seismic Network and Fiber‐Optic Cables

Abstract

A common challenge in acoustic meteoroid signal analyses is to discriminate whether the observed wavefield can be better described by line‐source or point‐source models. This challenge typically arises from a sparse availability of observations. In this work, we present an outstanding record of ground‐coupled waves from local large‐N seismic and distributed acoustic sensing (DAS) observations of a meteoroid in Iceland. Our complete data set includes additional regional stations located within 300 km of the meteoroid’s trajectory. The dense large‐N and DAS data allow identification of acoustic phases that are almost impossible to discriminate on sparser networks, including a weak late arrival resolved mostly only by DAS. Using this data set with a new Bayesian inversion model, we estimate the trajectory parameters of one fragment from the meteoroid. With these results we investigate its orbit in the solar system and propose a classification of the Icelandic event as a slow meteoroid of asteroidal origin with an energy on the order of 4–40 GJ, a probable size on the order of centimeters, and an orbit range consistent with the main asteroid belt.