  The Galileo Project's acoustic monitoring, omni-directional system (AMOS)
aids in the detection and characterization of aerial phenomena. It uses a
multi-band microphone suite spanning infrasonic to ultrasonic frequencies,
providing an independent signal modality for validation and characterization of
detected objects. The system utilizes infrasonic, audible, and ultrasonic
systems to cover a wide range of sounds produced by both natural and man-made
aerial phenomena. Sound signals from aerial objects can be captured given
certain conditions, such as when the sound level is above ambient noise and
isn't excessively distorted by its transmission path. Findings suggest that
audible sources can be detected up to 1 km away, infrasonic sources can be
detected over much longer distances, and ultrasonic at shorter ones. Initial
data collected from aircraft recordings with spectral analysis will help
develop algorithms and software for quick identification of known aircraft.
Future work will involve multi-sensor arrays for sound localization, larger
data sets analysis, and incorporation of machine learning and AI for detection
and identification of more types of phenomena in all frequency bands.
