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Abstract The grounding zone of a marine-terminating glacier, where ice begins to float, is a key control on glacier stability and ice discharge. Seismic deployments are a powerful means of studying both the geometry and processes of grounding zones; however, these regions are frequently inaccessible and dangerous for field work, and as a result are underrepresented in field studies. We report new data sets acquired at Eastwind Glacier, Antarctica, a relatively accessible grounding zone near McMurdo Station and Scott Base, as part of the Eastwind Glacier Geophysical Surveys on Top of an Antarctic Ice Shelf Transition, EGGS on TOAST, project. These data sets comprise a deployment of three-component seismic nodes and distributed acoustic sensing. The nodal deployment consisted of 330 nodes crossing the grounding zone, with all 330 nodes continuously recording for at least nine days, and 150 nodes recording for 19 days, in the austral summer of 2022/2023. Hammer-and-plate sources were recorded, with densely spaced shots along flow through the center of the array and shots located at every node. In 2023/2024, a 2.2 km fiber-optic cable was deployed for active source imaging by distributed acoustic sensing along and across flow, immediately downstream of the grounding line, for a period of 2 hr. Analysis of active source data recorded by the nodal array locates the point of flotation within the grounding zone and provides ice thickness estimates. We present initial analyses of passive source data, including icequake detection and location, and ambient noise analysis. We expect this data set to be of significant value to provide insight into fundamental grounding zone processes and as an event-rich cryoseismological data set on which to test novel methods of seismic analysis. 

Abstract Sample return capsules (SRCs) entering Earth’s atmosphere at hypervelocity from interplanetary space are a valuable resource for studying meteor phenomena. The 2023 September 24 arrival of the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer SRC provided an unprecedented chance for geophysical observations of a well-characterized source with known parameters, including timing and trajectory. A collaborative effort involving researchers from 16 institutions executed a carefully planned geophysical observational campaign at strategically chosen locations, deploying over 400 ground-based sensors encompassing infrasound, seismic, distributed acoustic sensing, and Global Positioning System technologies. Additionally, balloons equipped with infrasound sensors were launched to capture signals at higher altitudes. This campaign (the largest of its kind so far) yielded a wealth of invaluable data anticipated to fuel scientific inquiry for years to come. The success of the observational campaign is evidenced by the near-universal detection of signals across instruments, both proximal and distal. This paper presents a comprehensive overview of the collective scientific effort, field deployment, and preliminary findings. The early findings have the potential to inform future space missions and terrestrial campaigns, contributing to our understanding of meteoroid interactions with planetary atmospheres. Furthermore, the data set collected during this campaign will improve entry and propagation models and augment the study of atmospheric dynamics and shock phenomena generated by meteoroids and similar sources.