Source: Bolide over Arizona
Location: 33.8N 110.9W
Origin Time: 2016/06/02 ~ 10:56:32 UTC
Description: Broadband infrasound signal with durations up to 11 minutes
IMS Arrays: I57US, I58US, and I59US
UH Arrays: MAKUS
Data Quality: Signal at IMS stations I57US, I59US, and I58US with supporting PMCC results. UH station MAKUS station also had signal in the spectrograms, beam formed results, and PMCC results.
JPL reported that a ~0.49 KT fireball at 10:56:32 UTC (2 June) above Arizona. Expected back azimuths and travel times for several stations were calculated with this information (Table I).
Table I: Approximate arrival times are based on the estimated origin time of 2016/06/02 10:56:32 UTC and a location from http://neo.jpl.nasa.gov/fireballs/.
~Apparent slowness (s/km)
Data analysis is performed with INFERNO and array processing using the Progressive Multi-Channel Correlation (PMCC) method. Signal-to-noise is calculated for each element within the station, in a time window predicted by the origin time, range, and a celerity range of 0.25 to 0.45 km/sec. Hourly, automatic PMCC results are then checked with the event expected time and back-azimuth. Then a beam is constructed with the data along the expected back-azimuth and signal-to-noise is calculated for it. The event is later revisited with a manual PMCC run using optimized parameters.
Several infrasound stations investigated for the Arizona event (Figure 1).
The following figures show the signal captured by IMS stations (I57US, I59US, and I58US) and an UH station (MAKUS). Please note, other stations were processed but were not included in this report due to a lack of significant coherent signal.