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1. Large planets may not form fractionally large moons

   https://doi.org/10.1038/s41467-022-28063-8  

   Nakajima, Miki ; Genda, Hidenori ; Asphaug, Erik ; Ida, Shigeru ( December 2022 , Nature Communications)

   Abstract One of the unique aspects of Earth is that it has a fractionally large Moon, which is thought to have formed from a Moon-forming disk generated by a giant impact. The Moon stabilizes the Earth’s spin axis at least by several degrees and contributes to Earth’s stable climate. Given that impacts are common during planet formation, exomoons, which are moons around planets in extrasolar systems, should be common as well, but no exomoon has been confirmed. Here we propose that an initially vapor-rich moon-forming disk is not capable of forming a moon that is large with respect to the size of the planet because growing moonlets, which are building blocks of a moon, experience strong gas drag and quickly fall toward the planet. Our impact simulations show that terrestrial and icy planets that are larger than ~1.3−1.6 R ⊕ produce entirely vapor disks, which fail to form a fractionally large moon. This indicates that (1) our model supports the Moon-formation models that produce vapor-poor disks and (2) rocky and icy exoplanets whose radii are smaller than ~1.6 R ⊕ are ideal candidates for hosting fractionally large exomoons. 

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2. Floodplain Large Wood and Organic Matter Jam Formation After a Large Flood: Investigating the Influence of Floodplain Forest Stand Characteristics and River Corridor Morphology

   https://doi.org/10.1029/2020JF006011  

   Lininger, K. B. ; Scamardo, J. E. ; Guiney, M. R. ( June 2021 , Journal of Geophysical Research: Earth Surface)
3. Generating large volumes of crust-derived high δ18O rhyolites in the Chon Aike Silicic Large Igneous Province, Patagonia

   https://doi.org/10.1130/GES02551.1  

   Foley, Michelle L. ; Putlitz, Benita ; Baumgartner, Lukas P. ; Bégué, Florence ; Siron, Guillaume ; Kosmal, Andres ( May 2023 , Geosphere)

   The Jurassic Chon Aike Silicic Large Igneous Province (Patagonia and the Antarctic Peninsula) is dominated by voluminous, crust-derived magmas (235,000 km3) that erupted as predominately explosive silicic material over ~40 m.y. In this study, we combine petrological descriptions and bulk-rock major- and trace-element compositions with quartz oxygen-isotope measurements from multiple silicic units (primarily ignimbrites and some rhyolitic flows) from two of the five silicic formations in Patagonia. We have identified that quartz oxygen-isotope values are high (>9‰–12‰). Quartz phenocrysts analyzed by secondary ion mass spectroscopy (SIMS) are also homogeneous at the microscale with no measurable change in isotope value with respect to internal and often complex zoning textures. The ubiquity of widespread high δ18O rhyolites and their trace-element compositions support their origin from melting of a metasedimentary source with a similarly high δ18O value. Mass balance calculations require that an average of >75% melt derived from partial melting of the dominant basement lithology is needed to explain the isotopic and chemical composition of the rhyolites. The ideal P-T environment was identified by thermodynamic models for fluid-absent melting of graywackes at 900 °C and 5 kbar. Regional-scale crustal melting occurred during a widespread, high heat-flux environment within an extensional setting during the break- up of the Gondwanan supercontinent. The overlap of a unique tectonic and igneous environment, combined with a fertile crust dominated by graywacke and pelitic compositions in southern Patagonia, generated large volumes of some of the highest δ18O silicic magmas documented in the geologic record. 

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4. Generation of Large-Scale Gust Structures in a Large Boundary Layer Wind Tunnel: 3D Flow Measurement Experiments

   https://doi.org/10.17603/ds2-0m8r-my92  

   Mokhtar, Nasreldin O. ; Fernández-Cabán, Pedro L. ; Catarelli, Ryan A. ( July 2023 , Designsafe-CI)

   This dataset includes flow velocity time series collected in a large boundary layer wind tunnel (BLWT) to investigate the intensity of large-scale turbulent gust structures generated by a novel flow-control instrument. The work leveraged a multi-stage flow conditioning system consisting of an active multi-fan gust generator, termed flow field modulator (FFM), that operated in conjunction with an automated roughness element grid (called Terraformer). The primary goal of the study is to assess the effectiveness of the coupled flow conditioning system (FFM and Terraformer) for increasing and tuning large-scale (particularly near-surface) turbulent structures that will enable characterization of their impact on building loads at relatively large BLWT scales (1:50). The dataset can be used and compared against previously published velocity measurements collected using traditional BLWT flow conditioning approaches (i.e., no active control of large-scale turbulence). 

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5. Identification of switched autoregressive exogenous systems from large noisy datasets: Identification of switched autoregressive exogenous systems from large noisy datasets

   https://doi.org/10.1002/rnc.4968  

   Hojjatinia, Sarah ; Lagoa, Constantino M. ; Dabbene, Fabrizio ( January 2020 , International Journal of Robust and Nonlinear Control)