Analysis of a Multi‐Stage Sounding Rocket via Ground-­Based Infrasonic Observations

Abstract:

Infrasonic signals produced by a four-stage sounding rocket launched from the Alomar observatory in Norway were recorded at several nearby infrasound arrays. An array very near the launch pad detected infrasound due to the rocket during the full launch, while those further from the launch point were in an acoustic shadow zone while the source was at low altitudes. Analysis of the signals on all arrays found agreement with propagation modeling predictions, implying that signals from multiple arrays could provide a means to reproduce the trajectory of a rocket using infrasonic observations. Interestingly, high-altitude stage ignitions have been found to be very low amplitude in this particular data set, possibly due to inefficiency of the aeroacoustic source mechanism in the rarefied upper atmosphere.