genetic-algorithm-trajectory-inversion

MATLAB codes to invert for the trajectory of meteor. The trajecotry is constrained based on the parameters: vel (in m/s), x0, y0, gamma, delta, t0.

• vel -> speed
• gamma -> azimuth
• delta -> elevation angle
• (x0,y0) -> the termination point
• t0 -> the expected time at the termination point

Two Assumptions:

1. the meteor penetrates linearly through the atmosphere with a constant velocity
2. the shockwave speed of 320 m/s is uniform in the atmosphere

Run

run the main matlab script:

ga_test.m

• change the number of run numrun to considerably high value (e.g. 20) to estimate reliable output.
• change the lower and upper limits of the trajectory parameters.
• change the observed arrival times of the shockwaves, dobs in the script fit_arrival_times.m
• the coordinates of the stations are obtained directly from the sac headers of the seismograms. script: get_stations_coords.m

For details:

Kumar, U., Chao, B.F., Hsieh, Y. et al. A meteor shockwave event recorded at seismic and infrasound stations in northern Taiwan. Geosci. Lett. 4, 13 (2017). https://doi.org/10.1186/s40562-017-0079-2