HR: 14:40h
AN: U32B-04    [PDF]
TI: Infrasound from Bolides: Inverse Remote Sensing
AU: * ReVelle, D O
EM: revelle@lanl.gov
AF: Los Alamos National Laboratory, P.O. Box 1663, MS D401, Los Alamos, NM 87545 United States
AB: The entry of large meteor-fireballs (bolides) into the atmosphere generates numerous physical phenomena that allows its detection including the generation of substantial amounts of heat, light, propagating blast waves, dissociation, ionization, aerosols, remnant wake turbulence, upward propagating ionospheric waves, VLF radio wave emission, etc. The low frequency remnant of the blast wave at great range (from 10 Hz to as long as a few minutes in period) can be detected by ground-based infrasonic pressure sensor arrays at ranges of hundreds to tens of thousands of kilometers depending on the kinetic energy of the bolide and on local wind-noise. The multiple array detection allows the location of the source to be determined (latitude, longitude) with uncertainties in the determined great-circle bearing increasing substantially beyond about 10,000 km in range. A reverse ray tracing or ray-mode analysis can also allow the range and altitude of the source to be estimated as well even with data from only a single array. While these IMS on-going detection's will add new and different types of bolides to the already existing database regarding the global influx rate, the data can also be used to ascertain detailed properties of the bolide. Using this information in combination with realistic models of entry and possible satellite detection's, we can also infer detailed aspects about the bolide's properties. We will review this detection problem utilizing infrasound data from some recent events and in combination with ground-based cameras/radiometers detections.
DE: 3394 Instruments and techniques
DE: 6205 Asteroids and meteoroids
SC: U
MN: 2003 Fall Meeting