Meteoroid sonic shock-wave-generated seismic signals observed at a seismic array

Abstract

At approximately 04:20 local time (10:20 UT) on 19 September 1986, a local resident observed a meteor in the sky above Yellow-knife, North-west Territory, Canada. We subsequently found seismic signals, recorded at the Yellowknife seismic array in Northwest Territory, Canada, that coincided with the visual observation of the meteor in the sky overhead. The signals cannot be explained by any earthquake, explosion, or impact-generating mechanism. They are shown to be consistent with their having been generated by the shock wave created by the associated meteoroid as it passed through the atmosphere overhead. The meteoroid's trajectory and velocity, as inferred from the array records, is consistent both with the observed direction of travel of the meteoroid and independent seismic observations recorded at two single stations in the Northern Canadian seismic network.