Meteors and meteorites detected by infrasound

The Lamont-Doherty tripartite array of microphones has detected acoustic signals from meteors. These signals yield trace velocities which vary rapidly from supersonic to nearly infinite values for successive waves or wave groups, indicating a rapidly moving source. The trajectory is constructed on the basis of an assumption of reasonable path elevations. With a second array it would be possible to obtain more positive trajectory fixes and probable ground impact locations. Initial results suggest that most acoustic meteors are meteoritetype objects rather than the low-density objects commonly detected at high elevations by photographic and radio techniques.