학술논문

Acoustic signals of a meteoroid recorded on a large-N seismic network and fiber-optic cables
Document Type
Academic Journal
Source
Seismological Research Letters. 94(2A):731-745
Subject
04|Extraterrestrial geology
ablation
acoustical waves
arrays
atmospheric entry
COSEISMIQ
cryptoexplosion features
DEEPEN
distributed acoustical sensing
Europe
fiber optics
fireballs
geophones
Iceland
impacts
infrasonic waves
large-N seismic networks
meteoroids
moving source models
NORSAR
orbits
Raspberry Shakes
seismic networks
seismic sources
shatter cones
southwestern Iceland
trajectories
Western Europe
Language
English
ISSN
0895-0695
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.