Quick determination of bolide explosion locations using seismic and optic data
Abstract
Bright bolides entering in the atmosphere announce the entrance of meter-sized meteoroids often surviving as meteorites reaching the ground. To be able to find them it is necessary to locate quickly the position of the final explosion. This is usually done using optical sensors, but the bolides produce shock waves that can be detected by infrasound stations and, after coupling to the ground, also by seismic stations. The increasing availability of temporal seismic station deployments and the gathering of the records on permanent seismic networks can become a powerful tool to complement optical data, in particular for diurnal events or explosions located far from optical stations. We present here two examples of bolides exploding over NE Iberia that were reported in the Spanish Fireball and Meteorite Network (SPMN) catalogue with magnitudes -12 and -17 and recorded by temporary seismic arrays deployed near their entry trajectory. The location of the final explosions has been derived from the seismic data using a simplistic hypothesis and the codes used systematically for earthquake location. Although locating accurately the origin point of sonic waves is a complex task, our approach allows getting a quick location of the explosion location, with errors estimated in few kilometers, that appears as a useful tool to better define the search zone for eventual meteorites.