Ground Infrasound Observations from the OSIRIS-REx Sample Return Capsule Re-entry

The OSIRIS-REx Sample Return Capsule (SRC) re-entered the Earth's atmosphere on the morning of 24 September 2023. The SRC entered the atmosphere over the Pacific Ocean at a speed of over 43,000 km/hr and a few minutes later landed in Utah. The hypersonic entry of the SRC produced a shockwave as it entered the denser regions of the atmosphere that then decayed to infrasound (i.e., sound at frequencies below human hearing). Our team had microbarometers deployed on the ground near the border between Nevada and Utah to detect these infrasound waves. Most of the sensors were deployed at Wendover Airport that was nominally 58 km to the north of the SRC trajectory. Two of the sensors were deployed between the SRC trajectory and the airport. Three different sensor models (Chaparral Physics, GEM, and WERD) were deployed in close proximity to compare their performance. All the sensors observed an N-wave arrival followed by broadband coherent rumbling after the initial arrival. This presentation will present details of the deployment as well as preliminary results including beamforming of the received signals.