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    PIC simulation data for "Magnetic reconnection and instabilities in the Earth's quasi-parallel bow shock": foreshock region
    (2022) Bessho, Naoki
    Simulation data for a study of magnetic reconnection in foreshock waves, supported by a NASA grant 80NSSC20K1312, "Magnetic reconnection and instabilities in the Earth's quasi-parallel bow shock". Please see the data description file about details for the data.
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    Example code listings for the PhotoDissociation Region Toolbox
    (2022-08-31) Pound, Marc; Wolfire, Mark
    These are example code listings for the PhotoDissociation Region Toolbox (https://dustem.astro.umd.edu), and companion to the manuscript "The PhotoDissociation Region Toolbox: Software and Models for Astrophysical Analysis", by Pound & Wolfire (2022). These code snippets show typical ways to use the Toolbox and reproduce most of the figures in the manuscript. The code is written in Python 3 and demonstrate the pdrtpy Python package (https://pdrtpy.readthedocs.io).
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    Patchy Nightside Clouds on Ultra-hot Jupiters: General Circulation Model Simulations with Radiatively Active Cloud Tracers
    (AAS Journals, 2022-07-20) Komacek, Thaddeus; Tan, Xianyu; Gao, Peter; Lee, Elspeth
    The atmospheres of ultra-hot Jupiters have been characterized in detail through recent phase curve and low- and high-resolution emission and transmission spectroscopic observations. Previous numerical studies have analyzed the effect of the localized recombination of hydrogen on the atmospheric dynamics and heat transport of ultra-hot Jupiters, finding that hydrogen dissociation and recombination lead to a reduction in the day-to-night contrasts of ultra-hot Jupiters relative to previous expectations. In this work, we add to previous efforts by also considering the localized condensation of clouds in the atmospheres of ultra-hot Jupiters, their resulting transport by the atmospheric circulation, and the radiative feedback of clouds on the atmospheric dynamics. To do so, we include radiatively active cloud tracers into the existing MITgcm framework for simulating the atmospheric dynamics of ultra-hot Jupiters. We take cloud condensate properties appropriate for the high-temperature condensate corundum from CARMA cloud microphysics models. We conduct a suite of general circulation model (GCM) simulations with varying cloud microphysical and radiative properties, and we find that partial cloud coverage is a ubiquitous outcome of our simulations. This patchy cloud distribution is inherently set by atmospheric dynamics in addition to equilibrium cloud condensation, and causes a cloud greenhouse effect that warms the atmosphere below the cloud deck. Nightside clouds are further sequestered at depth due to a dynamically induced high-altitude thermal inversion. We post-process our GCMs with the Monte Carlo radiative transfer code gCMCRT and find that the patchy clouds on ultra-hot Jupiters do not significantly impact transmission spectra but can affect their phase-dependent emission spectra.
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    Dataset for "Stratigraphic Evidence for Early Martian Explosive Volcanism in Arabia Terra"
    (2021) Richardson, Jacob; Whelley, Patrick; Matiella Novak, Alexandra
    Seven Digital Elevation Models (DEMs) in the Arabia Terra region, Mars, were created using spatially overlapping images (i.e., "stereo images") from the Context Camera (CTX) aboard the Mars Reconnaissance Orbiter (MRO). Each DEM location was selected to spatially overlap hyperspectral data acquired by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) also aboard MRO. Elevation data from these DEMs were used to identify and measure geologic units that preserve minerals indicative of altered volcanic deposits. Stereophotogrammetry was performed using the Ames Stereo Pipeline toolkit v 2.6.0 and USGS ISIS Version 3.4.12.6662. Each DEM was aligned to the martian aeroid with Mars Orbiter Laser Altimeter Precision Experiment Data Records within the spatial footprint of the CTX DEM. DEM files are in the GeoTIFF raster format. Each raster has a sinusoidal projection coordinate system with a central longitude corresponding to the individual raster's center. For each CTX DEM, an ortho-rectified image was also produced. For naming conventions, references, and descriptions of each DEM site, see the enclosed readme.
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    CN coma rotational sequences for Comet 46P/Wirtanen
    (2020) Farnham, Tony
    This data collection contains animations showing the rotational sequences observed in Comet 46P/Wirtanen during its 2018/2019 apparition. The images were obtained with a narrowband CN filter, and enhanced with three different techniques (see description) to reveal the detailed structure in the coma. The sequences were phased to the periods derived from our rotation analyses.