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This dataset includes three-dimensional multitrack electrical conductivity measurements (3D ECM) results from measurements in the upper sections of the ALHIC2201 and ALHIC2302 large (241mm) diameter ice cores drilled in the Allan Hills blue ice area (76.73°S,159.36°E) in Victoria Land, East Antarctica. The data extends from the surface to 23.0 m depth in ALHIC2201 and from 8.5 m to 46.3 m depth in ALHIC2302. We include the raw 3D ECM data (AC and DC multitrack ECM measurements on perpendicular faces of a quarter-core cut) in CSV format and basic plots of this data. We also provide dip and dip direction estimates of the layering observed in each core section in a CSV table. 

Hyperspectral imaging (HSI) technology has been increasingly used in Earth and planetary sciences. This imaging technique has been successfully tested on ice cores using VNIR (visible and near-infrared, 380-1000 nm) (Garzonio et al., 2018) and near-infrared (900 - 1700 nm) (McDowell et al, 2023)  line-scan cameras. Results show that  HSI data greatly expand ice core line-scan imaging capabilities, previously used with gray or RGB cameras (see summary in Dey et al., 2023). Combinations of selected HSI bands from the hyperspectral data cube improve feature detection in ice core stratigraphy, and map distribution of volcanic material, dust, air bubbles, fractures, and ice crystals in ice cores. Captured spectral information provides unique fingerprints for specific materials present in ice cores. This method helps to guide ice core sampling because it provides non-destructive, rapid visualization of microstructural properties, layering, bubble contents, increases in dust, or presence of  tephra material. Precise identification of these atmospheric components  is important for understanding past climate drivers reconstructed from ice cores. As part of the COLDEX project (Brook et al., this meeting) we adapted the SPECIM SisuSCS HSI system for ice core imaging. The ice core scanning system is housed inside the ca. -20ºC main NSF ICF freezer, and externally computer-controlled. The operator monitors scanning operations and communicates with personnel inside of the freezer via radio.  The system is equipped with a SPECIM FX10 camera that measures up to 224 bands in the VNIR range. We modified the ice core holder tray and installed a heated enclosure for the camera. The system uses SCHOTT DCR III Fiber Optic light sources with an OSL2BIR bulb from Thorlabs. IR filters are removed to extend the light spectral range beyond the 700 nm limit without heating the ice core surface during rapid (<5 minutes) scanning of an entire meter-long section. Emitted light enters ice at a 45º angle from two top and two bottom light sources. To calibrate absolute reflectance we use three Spectralon panels with 100, 50 and 20% reflectance values with every scan as well as several secondary reflective standards and USAF targets for geometric corrections. We are developing Python-based open source data processing routines and currently comparing HSI data with existing ice core physical and chemical measurements. The goal is to fully integrate the ice core HSI system with ice core processing at the NSF ICF. Dey et al., 2023. Application of Visual Stratigraphy from Line-Scan Images to Constrain Chronology and Melt Features of a Firn Core from Coastal Antarctica. Journal of Glaciology 69(273): 179–90. https://doi.org/10.1017/jog.2022.59.Garzonio et al., 2018. A Novel Hyperspectral System for High Resolution Imaging of Ice Cores: Application to Light-Absorbing Impurities and Ice Structure. Cold Regions Science and Technology 155: 47–57. https://doi.org/10.1016/j.coldregions.2018.07.005.McDowell et al., 2023. A Cold Laboratory Hyperspectral Imaging System to Map Grain Size and Ice Layer Distributions in Firn Cores. Preprint. Ice sheets/Instrumentation. https://doi.org/10.5194/egusphere-2023-2351. 

Abstract Located on the campus of the Thacher School in Southern California, the Thacher Observatory has a legacy of astronomy research and education that dates back to the late 1950s. In 2016, the observatory was fully renovated with upgrades including a new 0.7 m telescope, a research grade camera, and a slit dome with full automation capabilities. The low-elevation site is bordered by the Los Padres National Forest and therefore affords dark to very dark skies allowing for accurate and precise photometric observations. We present a characterization of the site including sky brightness, weather, and seeing, and we demonstrate the on-sky performance of the facility. Our primary research programs are based around our multi-band photometric capabilities and include photometric monitoring of variable sources, a nearby supernova search and followup program, a quick response transient followup effort, and exoplanet and eclipsing binary light curves. Select results from these programs are included in this work which highlight the broad range of science available to an automated observatory with a moderately sized telescope.