bluuebunny/crossref_metadata_2025 huggingface dataset:
Expressive flexibility and resilience among U.S. military college students: Evaluating the enhancing and suppressing of emotions and resilience
Authors: Georgoulas-Sherry Vasiliki
Published: October 2020

Significant research has confirmed the necessity to better comprehend psychological constructs that are essential in predicting and influencing human performance, in particular, assessing expressive flexibility and resilience. However, limited research has investigated the relationships that exist between these two constructs that are critical protective factors in facilitating the mental health and the well-being of individuals. Through a number of structural equation modeling (SEM) techniques, the current endeavor evaluates this gap to assess the relationship between these two constructs. Utilizing a military student sample from a private U.S. military university (N = 107), participants completed the Resilience Scale for Adults (RSA) and the Flexible Regulation of Emotional Expression (FREE) scale. Correlations matrixes reported positive relationships between expressive flexibility and resilience. Confirmatory factor analyses (CFAs) revealed a bi-factor models of expressive flexibility and resilience. Additional CFAs revealed a two-factor model structure between expressive flexibility and resilience. Implications for future work are offered.
Performance of Urban Corridor Using Speed Profile Data of Automobile
Authors: Kumar T. Vijay , Manghat Drisya , Geetha L. , Das Vivek R.
Published: October 2020

The level of service on urban roads quality experienced by the drivers will be varying it is difficult to study the variations due to heterogeneous traffic flow conditions of Indian urban roads. As per TRB, 2010 macroscopic traffic flow parameters are found to be deficient in capturing the quality of service on urban roads experienced by users. Hence the objective of the study is to develop new methodology to evaluate the urban roads in heterogeneous traffic conditions considering the microscopic parameters of traffic flow in a four-lane divided urban corridor. The speed profile of the motorised two-wheelers both in free flow and peak flow were collected from the urban corridor of Bangalore Karnataka, India. Using GPS based mobile application. From the speed profile data, the speed variation characteristics were studied. The various speed indices considered in the study are VN (Velocity noise), CV (Co-efficient of variation), AN (Acceleration noise), and MVG (Mean Velocity Gradient). The CV is considered as the measure of effectiveness, higher the CV more will be the variation of quality experienced by the road users.
Photographs of a neighborhood’s identity.
Authors: Funaro Fernando
Published: October 2020

Based on an investigation located in a railway district from an average sized city in the province of Buenos Aires, Argentina, the article suggests an analysis of the relationships between social memory processes and the construction of urban-neighborhood identities, and the production and treatment of photographic images. Through an audiovisual investigation, the uses and the production of photographs are addressed in the critical interventions of some social actors related to the neighborhood history, which intend to interpellate hegemonic narratives both at the local level and concerning broader contexts. Both used and produced images respond to a set of demands that claim, among others, measures of patrimonial protection in the neighborhood and the restitution of the passenger train service.
ANALISIS KINERJA GURU SMK NEGERI 1 GEDONG TATAAN KABUPATEN PESAWARAN
Authors: Habe Hazairin
Published: October 2020

The problem in this study is whether motivation and Managerial Supervision affect teacherperformance at SMK Negeri 1 Gedong Tataan Kabupaten Pesawaran. This study aims to determine theeffect of motivation and Managerial Supervision on teacher performance. The hypothesis formulated isthat there is an influence of motivation and managerial supervision on teacher performance bothpartially and simultaneously. The sample used in this study amounted to 95 teachers.The results of partial hypothesis testing prove that motivation affects teacher performance, aswell as managerial supervision has a positive effect on teacher performance. Hypothesis testingsimultaneously motivation variables and managerial supervision variables have a positive effect onteacher performance. The results of the determination test show that simultaneously the teacherperformance variables are able to be explained by motivation variables and Managerial Supervision of85.3%, the remaining 14.7% are other variables not examined.
ANALISIS KUALITAS AUDITOR DAN FAKTOR YANG MEMPENGARUHINYA (Studi pada Auditor Pemerintah di BPKP Perwakilan Provinsi Lampung)
Authors: Wati Hestin Ratna , Akadiati Victoria Ari Palma
Published: October 2020

The purpose of this study is to obtain empirical evidence to be known and analyzed about theinfluence of expertise, independence and ethics on audit quality in Government Auditors at BPKPRepresentatives of Lampung Province. Expertise is the ability of an auditor, the independence of mentalattitudes that can not be influenced by others, the ethics of a set of principles or values. This researchwas conducted at BPKP Lampung Province Representative.Sampling technique using non probability sampling with purposive sampling method, thesample used as much as 52 respondents. This research includes quantitative research. Using multiplelinear regression analysis. The results of this study show (1) Expertise affect the Quality Audit, (2)Independence affects Quality (3) Ethics does not affect the Quality Audit (4) Expertise, Independenceand Ethics affect the Quality Audit
ANALISIS PERTUMBUHAN PENJUALAN, PROFITABILITAS DAN LIKUIDITAS TERHADAP KINERJA PERUSAHAAN OTOMOTIF YANG TERDAFTAR DI BURSA EFEK INDONESIA
Authors: Yuniastuti Rina Milyati
Published: October 2020

This research aims to determine the effect of partial sales growth on company performance, theinfluence of profitability on company performance and also the effect of liquidity on companyperformance and to know the simultaneous influence of sales growth, profitability and liquidity oncompany performance. which is listed on the Indonesian stock exchange. As for the results of this studyit turns out that both partially and simultaneously have an effect. This means that sales growth,profitability and liquidity have a very big role in the company's performance.
PENGUJIAN EFISIENSI PASAR BENTUK LEMAH PADA PASAR MODAL INDONESIA PERIODE 2014-2017
Authors: Yulianti Eka , Jayanti Dwi
Published: October 2020

Investigate the current consumption of assets for the benefit of the future. The investment canbe done by only one in the capital market which means that the investment is invested in the initialcapital assets. Profit or the same value is aimed at the investor's main interest in investing not releasedfrom risk money. Such risks are inevitably uncertain about information movement in the stock market.Relevant information available can be used as a basis for making decisions when to buy shares orretain holdings of shares. In addition, information can also be a basis for consideration when to releaseshares or not to buy shares at all. This information relates to Efficient Market Hypothesis (HPE) whichcontinues to research in financial markets. One of the forms of the Efficient Market (HPE) hypothesis isthat market efficiency is a weak form that is examined in this study. This market efficiency form isrelated to random walk theory which assumes that past data is not related to present value.
El derecho a la salud sexual y reproductiva en la pandemia del COVID-19 y la violencia estructural de género
Authors: Vargas-Zafra Lupe
Published: October 2020

La discriminación estructural, es el conjunto de prácticas reproducidas por patrones socioculturales instalados en las personas, las instituciones y la sociedad en general. Tiene como uno de los efectos a la vulneración de los derechos a la salud sexual y salud reproductiva, que se expresa en prácticas excluyentes y violentas, quebrantando así el derecho humano a una vida libre de violencia. El Índice de Desigualdad de Género (IDG) mide las brechas de género en el Perú, aborda esta problemática en el aspecto de la salud sexual y reproductiva como una variable importante del desarrollo humano. La situación social y económica causada por la pandemia del COVID -19 en el Perú ha generado incremento de la desigualdad y desventaja de las mujeres para asumir sus derechos sexuales y reproductivos, situación que se evidencia con el incremento con la violencia física y psicológica, el embarazo en adolescentes y la muerte materna.
Autocratization by Decree: States of Emergency and Democratic Decline
Authors: Lührmann Anna , Rooney Bryan
Published: October 2020

States of emergency grant chief executives the power to bypass democratic constraints in order to combat existential threats. As such, they are ideal tools to erode democratic institutions while maintaining the illusion of constitutional legitimacy. Therefore, states of emergency should be associated with a heightened risk of autocratization – a decline in a regime's democratic attributes. Despite this theoretical link and the contemporary relevance of both autocratization and states of emergency, no prior study has empirically tested this relationship. This article tests this relationship using data on sixty democracies for 1974 to 2016. We find that democracies are 75 percent more likely to erode under a state of emergency. This evidence strongly suggests that states of emergency circumvent democratic processes in ways that might promote democratic decline.
Post-Covid-19 and local economic development (LED): sharing experiences from Ghana
Authors: Bilattey Bimi
Published: October 2020

The emergence of the novel Coronavirus (COVID-19) pandemic has brought many development activities to a standstill. The disruption to economic and other livelihood activities is unprecedented. Within the Ghanaian landscape, COVID-19 has become an overarching pandemic that has engulfed every facet of the national economy. The pandemic has exposed existing vulnerabilities in our communities that must be addressed to ensure resilient recovery. Serious economic challenges lie ahead that risk exacerbating poverty and unemployment, with national and local governments increasingly struggling to meet the needs of citizens. Addressing these challenges will require a paradigm shift in the way local businesses are modelled, livelihoods are shaped and how jobs are created. This is where Local Economic Development (LED) as a driver of innovation, employment and growth presents a great opportunity.
The AEMET-γSREPS over the Antarctic Peninsula and the impact of kilometric-resolution EPS on logistic activities on the continent
Authors: Gonzalez Sergi , Callado Alfons , Martínez Mauricia , Elvira Benito
Published: October 2020

Abstract. Kilometric-resolution Ensemble Prediction Systems (EPSs)
will be the new state-of-the-art forecasting tools for short-range
prediction in the following decade. Their value will be even greater in
Antarctica due to the increasingly demanding weather forecasts for logistic
services. During the 2018–2019 austral summer (1 December–31 March),
coinciding with the Southern Hemisphere Special Observation Period of the
Year of Polar Prediction (YOPP), the 2.5 km AEMET-γSREPS was
operationally integrated over the Antarctic Peninsula. In particular, the
Antarctic version of γSREPS comes up with crossing four
non-hydrostatic convection-permitting NWP models at 2.5 km with three global NWP driving models as boundary conditions. The γSREPS forecasting system has been validated in comparison with ECMWF EPS. It is concluded that γSREPS has an added value to ECMWF EPS due to both its higher resolution and its multi-boundary conditions and multi-NWP model approach. γSREPS performance has a positive impact on logistic activities at research stations and its design may contribute to polar prediction research.
Intersecting Methane Production and Oxidation Zones in Freshwater Sediments
Authors: Chen Xueping , Yu Juan , Liu Lihua , Sun Jing , Bai Fayan , Yang Ming , Chen Zheng , He Chiquan , Liu Xiaoyan , Bai Shuang , Wang Fushun
Published: October 2020

Abstract. Methane is produced and emitted when organic carbon accumulates in the sediments of reservoirs. Before being released into the water body, methane can be oxidised microbially by multiple electron accepters in the sediment, and which were traditionally considered to be spatially separated from methanogens. This study provides geochemical and microbiological evidence to firstly demonstrate that methane production and oxidisation zones intersected each other in the sediment of a freshwater reservoir. Methanogens were distributed along the sediment depth profile. Hydrogenotrophic Methanomicrobiales were found to be responsible for methane production in the upper layer (
Sample return of primitive matter from the outer Solar System
Authors: Vernazza Pierre , Beck Pierre
Published: October 2020

The last thirty years of cosmochemistry and planetary science have shown that one major Solar System reservoir is vastly undersampled in the available suite of extra-terrestrial materials, namely small bodies that formed in the outer Solar System (>10AU). Because various dynamical evolutionary processes have modified their initial orbits (e.g., giant planet migration, resonances), these objects can be found today across the entire Solar System as P/D near-Earth and main-belt asteroids, Jupiter and Neptune Trojans, comets, Centaurs, and small (diameter
Asteroid multiplicity detection in Gaia DR2
Authors: Santana-Ros Toni , Cellino Alberto , Campo-Bagatin Adriano , Benavidez Paula , Alvarez-Candal Alvaro , Tanga Paolo
Published: October 2020

Binary asteroids are of special importance in planetary science as they provide direct measurements of the body's bulk mass and density. The main way to discover these systems is by detecting their mutual events in the lightcurves. There are almost 400 asteroids with satellites known as of writing this. Gaia Data Release 2 (Gaia DR2) contains sparse disk-integrated brightness measurements for more than 14.000 asteroids spanned over 22 months of observations. We have studied these data to detect multiple asteroid system candidates. For this work we have used the inversion genetic algorithm which provides best fit solutions for asteroids' spin and shape parameters. In order to cope with the limited viewing geometries of a large majority of asteroids, we have upgraded the inversion algorithm to combine Gaia DR2 with other ground-based data such as the Lowell Observatory photometric database. In the near future we envisage a great increase on the number of multiple asteroid discovery by analysing the data of large sky surveys. Particularly interesting will be the analysis of Gaia DR3 (expected for H2 2021) which will contain data for more than 100.000 asteroids.
Asteroid masses obtained with INPOP planetary ephemerides
Authors: Fienga Agnes , Avdellidou Chrysa , Hanus Josef
Published: October 2020

We present here masses of 103 asteroids deduced from their perturbations on the
orbits of the inner planets, in particular Mars and the Earth. These determinations and the
INPOP19a planetary ephemerides are improved by the recent Mars orbiter navigation data
and the updated orbit of Jupiter based on the Juno mission data. More realistic mass estimates
are computed by a new method based on random Monte-Carlo sampling that uses up-to-date
knowledge of asteroid bulk densities. We provide masses with uncertainties better than 33%
for 103 asteroids. Deduced bulk densities are consistent with those observed within the main
spectroscopic complexes.
NUCLIO science communication: an ongoing effort to spread the word
Authors: Saraiva Jose , Direitinho Teresa , Doran Rosa
Published: October 2020

In the early 2000’s, a group of astronomers working in Portugal, aware of the deficit in science literacy in the country, decided to create an organization devoted to science communication and outreach. And so, NUCLIO was born. Naturally, the early efforts of this group were focused in the field of astronomy, but soon other fields were included in the endeavour. Through the years, NUCLIO grew and became an important player in the field of education, joining many international projects and creating links with educational institutions all over the world.Early in its history, NUCLIO created Portal do Astrónomo, a portal with many diverse sections, trying to spread information by translating news, giving space to scientists to talk about their research and fields of interest, answering questions from the public, and using the available technological means to reach its audience. Given the scarcity of Portuguese-language sites disseminating science, the Portal collected large numbers of readers, namely in Brazil.In recent years, with the advent of PLOAD (Portuguese Language Office of Astronomy for Development), a new need was felt: reaching out to the Portuguese-speaking communities in Africa and elsewhere. Tightening collaboration with other communicators in Brazil and African countries has become a goal for NUCLIO and the Portal. Another goal is becoming more involved in the efforts to make people all over the world aware of the need to protect the planet and its global environment, and of the fact that we all belong to one and the same species, facing a common future.The current Portal features Space Scoop and other astronomical news translations, but also original contributions in columns such as the Theme of the Month and others, where different science themes are tackled; the target audience is now mainly teachers and students, given the closer ties with this field, and the fact that new groups directed at the general public have come into existence.We are striving to become ever more inclusive and global (recently we started including English versions of some texts in the Portal), and to take advantage of new tools for communication, like producing webinars and online courses. A new section was recently created where simple astronomical challenges are proposed, demanding some interaction and commitment from the readers.In the meantime, NUCLIO has also invested in social media, creating connections between the Portal and Facebook, for instance. Thus, the publications in Portal can reach new audiences and in fact help in weaving a close network between the many projects in which NUCLIO is involved and the public.We feel that in this globalized but increasingly selfish world it is still important to spread information about science, and at the same time consolidate and educate the audience, so that a more informed public can become aware of the role of science and education in reaching a sustainable and solidary society and an environmentally sound planet.
A NEO Physical Properties database within the NEOROCKS EU project
Authors: Giunta Alessio , Giardino Marco , Perozzi Ettore , Polenta Gianluca , Zinzi Angelo ,   NEOROCKS
Published: October 2020

The advent of new wide field, ground-based and multiwavelength space based sky surveys will lead to a large amount of data that needs to be efficiently processed, archived and disseminated. In addition, differently from astrometric observations which have a centralized data repository acting under IAU mandate (the MPC), the outcome of ground-based NEO observations devoted to NEO physical characterization are sparsely distributed. It appears then desirable to have data on NEO physical characterization available through a centralized access able to guarantee their long-term archiving, as well as to ensure the maintenance and the evolution of the corresponding data products.   Within the NEOROCKS EU project (“The NEO Rapid Observation, Characterization and Key Simulations” - SU-SPACE-23-SEC-2019 from the Horizon 2020), as part of WP5 (Data Management) activities, we propose the implementation of a unique NEO Physical Properties database hosting all different data products resulting from NEO observations devoted to physical characterization, in order to ensure an efficient data products dissemination and their short/long-term storage and availability. The NEOROCKS database, will be designed by means of an EPNCore derived data model (see [1]) ready for the EPN-TAP service implementation, and thus able to store, maintain and regularly update all different levels of processing, from raw data to final products (e.g. size, rotation, spectral type) beyond the duration of the project as an reliable source of services and data on NEO physical properties hosted at ASI SSDC. The NEOROCKS database will import NEO orbital elements from the Near-Earth Object Dynamics Site (NEODyS), while NEO physical parameters will be partly provided by NEOROCKS users, partly imported from external data source. In particular, the NEO physical properties database available at the ESA NEO Coordination Center, hosting since 2013 the legacy of the European Asteroid Research Node (EARN) and which will host Solar System Objects (SSO) NEO physical properties in the Gaia DR3 expected for the second half of 2021, will be imported and integrated into the NEOROCKS Physical Properties Database. Thus, a single query interface will allow to display both dynamical and physical properties of any given NEO, or to search for samples within the NEO population satisfying certain requirements (e.g. targets for astronomical observations and mission analysis). Acknowledgements: The LICIACube team acknowledges financial support from Agenzia Spaziale Italiana (ASI, contract No. 2019-31-HH.0 CUP F84I190012600).  References [1] Erard S., Cecconi B., Le Sidaner P., Berthier J., Henry F., Molinaro M., Giardino M., Bourrel N., Andre N., Gangloff M., Jacquey C., Topf F. 2014. The EPN-TAP protocol for the Planetary Science Virtual Observatory (2014). Astronomy And Computing, vol. 7-8, p. 52-61, ISSN: 2213-1337, doi: 10.1016/j.ascom.2014.07.008
Experience of DAN investigation of subsurface water on Mars onboard the rover Curiosity for the future ADRON-RM experiment on the ExoMars rover
Authors: Nikiforov Sergei , Mitrofanov Igor , Litvak Maxim , Djachkova Maya , Golovin Dmitry , Lisov Denis , Malakhov Alexey , Mokrousov Maxim , Sanin Anton , Tretyakov Vladislav
Published: October 2020

     Remote neutron sensing onboard martian rovers is an advanced technique in planetary science. Such measurements provide investigations on hydrogen abundances and elements with high thermal neutron absorption cross sections down to ~60 cm of subsurface [1]. The presence of hydrogen (mostly water/ice) in subsurface significantly influences the neutron leakage spectrum due moderation and thermalization through collisions with hydrogen nuclei. As a result, the variations of neutron flux detected onboard in different energy bands correlate with subsurface hydrogen/water abundance.     Dynamic Albedo of Neutrons (DAN) is the first neutron spectrometer installed on the NASA’s rover [2]. More than 7 years, NASA rover is successfully traversing across Mars surface exploring Gale crater. Adron-RM is the next generation neutron spectrometer, which is a part of the ExoMars 2022 rover payload [3].     This work will present scientific potential of remote neutron technique to distinguish local features in martian subsurface, based on DAN findings. In addition, we will provide Adron-RM measurement schematic and scientific potential on investigations in the area of the ExoMars 2022 landing site.     References[1] Nikiforov, S. Y., et al., (2020). Assessment of water content in martian subsurface along the traverse of the Curiosity rover based on passive measurements of the DAN instrument. Icarus, 346, 113818. https://doi.org/10.1016/j.icarus.2020.113818[2] Mitrofanov, I. G., et al., (2012). Dynamic Albedo of Neutrons (DAN) experiment onboard NASA’s Mars Science Laboratory. Space Science Reviews, 170(1–4), 559–582. https://doi.org/10.1007/s11214-012-9924-y[3] Mitrofanov, I. G., et al., (2017). The ADRON-RM Instrument Onboard the ExoMars Rover. Astrobiology, 17(6–7), 585–594. https://doi.org/10.1089/ast.2016.15
Fe I and Fe II in the atmosphere of Ultra-hot Jupiter MASCARA-2b
Authors: Stangret Monika , Casasayas-Barris Núria , Palle Enric , Yan Fei , Sánchez-López Alejandro , López-Puertas Manuel
Published: October 2020

Thanks to the different Doppler velocities of the Earth, the host star and the planet using high-resolution spectroscopy we are able to detect and characterise exoplanetary atmospheres. Exoplanetary signal is buried in the residual noise, however by preforming cross-correlation of atmospheric transmission model and hundreds of atmospheric lines the signal can be increase. Studying the atmospheres of ultra-hot Jupiters, objects with the temperature higher than 2200K which orbit close to their host stars, gives us great laboratory to study chemistry of the exoplanets. MASCARA-2b also known as KELT-20b with the temperature of 2230 K is a perfect example of ultra hot Jupiter. We studied this object using three transit observations obtained with HARPS-North. Using cross-correlation method we detected strong absorption of Fe I and FeII, which agrees with theoretical models. Additionally, because of the fast rotation of the star, the crosscorrelation residuals show strong Rossiter-MacLaughlin effect.
Small body exploration in China
Authors: Huang Jiangchuan , Zhang Xiaojing , Wang Tong , Huo Zhuoxi , Shi Xian , Meng Linzhi
Published: October 2020

The past twenty years have seen an evolution in the definition and categorization of small bodies in the Solar System. While new types of bodies are being discovered at an increasing pace, objects familiar to us have been rediscovered with traits previously unknown, resulting in “hybrid” bodies like “Main-belt comets” or “active asteroids” [1]. New knowledges of small bodies are essential to further our understanding of the solar system as they directly shed light on planetary formation and evolution scenarios, the distribution and migration of water, and the emergence of life. To get a full picture of these small bodies, it is necessary to carry out detailed and comprehensive investigations, especially with dedicated space missions. As demonstrated by the success of a number of such missions recently completed and ongoing, a growing consensus is emerging that future missions should: 1) cover a diversity of targets, especially those never visited before; 2) characterize the structure and composition of the target body with highest possible resolution. The first Chinese small body mission is designed to take on both challenges by performing sample return from a quasi-satellite of the Earth—2016 HO3 and visiting for the first time a “main-belt comet”--133P/Elst-Pizarro.In April 2019, CNSA released an open call of onboard opportunity for an asteroid exploration mission [2]，which encourages international cooperation. This asteroid exploration mission is characterized by multi-task, multi-target and multi-mode (e. g. joint exploration by multiple devices, landing and sampling etc.). On the basis of feasibility demonstration, design research and key techniques research, various work of the mission is currently in progress, such as the scientific research of small celestial particles, that is, combining remote sensing and surface in-situ measurement data and features of different scales (sub-millimeter to decimeter) to obtain clues of composition and evolution of small bodies.  [1] Hsieh, Henry H., David C. Jewitt, and Yanga R. Fernández. The Astronomical Journal 127(5):2997. (2004).[2] http://www.cnsa.gov.cn/n6758823/n6758839/c6805886/part/6780392.pdf
Measuring and modeling the Balmer series in hot gaseous giant exoplanets
Authors: Wyttenbach Aurélien , Mollière Paul , Ehrenreich David , Cegla Heather , Bourrier Vincent , Lovis Christophe , Pino Lorenzo , Allart Romain , Seidel Julia , Hoeijmakers Jens , Nielsen Louise , Lavie Baptiste , Pepe Francesco , Bonfils Xavier , Snellen Ignas
Published: October 2020

Atmospheric escape rate is a key parameter to measure in order to understand the evolution of exoplanets. In this presentation, we will show that the Balmer series, observed with high-resolution transmission spectroscopy, is a precise probe to measure exoplanet evaporation, especially for ultra hot Jupiters orbiting early-type star. These hot gaseous giant exoplanets (such as KELT-9 b) are presumed to have an atmosphere dominated by neutral and ionized atomic species. In particular, hydrogen Balmer lines have been detected in some of their upper atmospheres, suggesting that hydrogen is filling the planetary Roche lobe and escaping from these planets. Here, we will present new significant absorptions of the Balmer series in the KELT-9b atmosphere obtained with HARPS-N. The precise line shapes of the Hα, Hβ, and Hγ absorptions allow us to put constraints on the thermospheric temperature. Moreover, the mass loss rate, and the excited hydrogen population of KELT-9 b are also constrained, thanks to a retrieval analysis performed with a new atmospheric model (the PAWN model). We retrieved a thermospheric temperature of T = 13 200+800-720 K and a mass loss rate of log10(MLR) = 10^(12.8+-0.3) g/s when the atmosphere was assumed to be in hydrodynamical expansion and in local thermodynamic equilibrium (LTE). Since the thermospheres of hot Jupiters are not expected to be in LTE, we explored atmospheric structures with non-Boltzmann equilibrium for the population of the excited hydrogen. We do not find strong statistical evidence in favor of a departure from LTE. However, our non-LTE scenario suggests that a departure from the Boltzmann equilibrium may not be sufficient to explain the retrieved low number densities of the excited hydrogen. In non-LTE, Saha equilibrium departure via photo-ionization, is also likely to be necessary to explain the data.
Unveiling cloudy exoplanets: the influence of cloud model choices on retrieval solutions
Authors: Barstow Joanna
Published: October 2020

A substantial fraction of transiting exoplanets have some form of aerosol present in their atmospheres. Transit spectroscopy, especially of hot Jupiters, has provided evidence for this, in the form of steep downward slopes from blue to red in the optical part of the spectrum, and muted gas absorption features throughout. Studies analysing the atmospheres of these planets must therefore consider the presence of aerosol.However, clouds and hazes are complex, and the transit spectra that are currently available allow us to constrain only limited properties of cloud and haze. Retrieval models – fast, parametric radiative transfer models coupled with an inversion algorithm – are typically used to analyse transit spectra, but these rely on minimising the number of variables to ensure rapid convergence. Optimising aerosol parameters to maximise constraints on cloud structure, whilst avoiding overfitting, is therefore a necessary step.In this presentation, I investigate a range of aerosol parameterisations from the literature (Figure 1), and examine their effects on retrievals from transmission spectra of hot Jupiters HD 189733b (Figure 2) and HD 209458b. Regardless of the parameterisation used, results qualitatively agree for the cloud/haze itself, and using multiple approaches provides a more holistic picture. The retrieved H2O abundance is also robust to assumptions about aerosols. Additionally, strong evidence emerges that aerosol on HD 209458b covers less than half of the terminator region, but the situation for HD 189733b is less clear (Barstow 2020).References:Barstow J. K., Aigrain S., Irwin P. G. J., Sing D. K., 2017, ApJ, 834, 50Barstow J. K., 2020, arxiv:2002.02945Fisher C., Heng K., 2018, MNRAS, 481, 4698Pinhas A., Madhusudhan N., Gandhi S., MacDonald R., 2019, MNRAS, 482, 1485Sing D. K., et al., 2016, Nature, 529, 59Tsiaras A., et al., 2018, AJ, 155, 156 
Color Effects of Textural Variations on Bennu: Comparison of Analog Laboratory Mixtures with OSIRIS-REx Data
Authors: Sen Antara , Clark Beth E. , Cloutis Edward A. , Hendrix Amanda R. , DellaGiustina Daniella N. , Applin Daniel M. , Connell Stephanie , Parkinson Alexis , Ferrone Salvatore
Published: October 2020

OSIRIS-REx is a sample return mission to near-Earth Asteroid (101955) Bennu (Lauretta et al. 2017). The asteroid is spectrally classified as a B-type (Clark et al. 2011), and phyllosilicates similar to those found in carbonaceous chondrites have been detected on its surface (Hamilton et al. 2019).  Bennu has a relatively flat (and blue) reflectance spectrum in the 0.4 to 3.7 micron spectral range and has a low albedo of ~4.5% (Golish et al. 2020).Bennu has a rough and rocky surface. Imaging data from the OSIRIS-REx Camera Suite (OCAMS; Rizk et al. 2018) reveals that boulders in the size range from 1 to 10 meters dominate the surface (Lauretta et al. 2019; DellaGiustina and Emery et al. 2019). Observed boulder textures range from smooth to hummocky and breccia-like (Walsh et al. 2019; DellaGiustina and Emery et al. 2019). The smoother rocks appear to be smaller, brighter, and more angular, while the rougher rocks appear to be larger, darker, and highly textured.  Because spectral variations on Bennu are subtle and associated with albedo (Clark et al. 2019), the question arises: Could the observed color variations be due to texture variations alone, or are space-weathering variations required to explain the observations?  To isolate the spectral effects of texture on the spectral properties of Bennu, we first simulate Bennu’s spectrum using a two-component mixture, then we check to see whether texture changes in this analog can account for the observed color and albedo trends.  Simulated Bennu Spectral Analog: We synthesized physical mixtures of saponite (SAP105 with ~25 wt.% dolomite) with two forms of carbon:
Trident: A Mission to Explore Triton, a Candidate Ocean World
Authors: Howett Carly , Procktor Louise , Mitchell Karl , Bearden David , Smythe William
Published: October 2020

Triton: Scientific MotivationNeptune’s moon Triton is one of the most interesting and surprising targets observed by Voyager. During its distant flyby in 1989, Voyager 2 captured a series of images, mostly of the southern, sub-Neptune hemisphere, establishing Triton as one of a rare class of solar system bodies with a substantial atmosphere and active geology. It is believed that Triton began as of a Dwarf Planet originating in the KBO, and subsequently captured by Neptune. It nor exists as Neptune’s icy satellite, and is subject to a tidal, radiolytic, and collisional environment. It is this duality as both captured dwarf planet and large icy satellite that has undergone extreme collisional and tidal processing that gives us a unique target for understanding two of the Solar System's principal constituencies and the fundamental processes that govern their evolution. Thus, comparisons between Triton and other icy objects will facilitate re-interpretation of existing data and maximize the return from prior NASA missions, including New Horizons, Galileo, Cassini and Dawn.Triton’s surface and atmosphere are remarkable, but poorly understood. They hint at on-going geological activity, suggesting an active interior and a possible subsurface ocean. Crater counts suggest a typical surface age of
Six hundred 1-km retrograde jovian irregular moons
Authors: Ashton Edward , Beaudoin Matthew , Gladman Brett
Published: October 2020

We have searched a 2010 archival data set from the Canada-France-Hawaii Telescope for very small (km-scale) irregular moons of Jupiter in order to constrain the size distribution of these moons down to radii of ~400m, discovering 53 objects which are moving with Jupiter-like on-sky rates and are nearly certainly irregular moons. The four brightest detections, and seven in total, were all then linked to known jovian moons. Extrapolating our characterized detections (those down to magnitude mr=25.7) to the entire retrograde circum-jovian population, we estimate the population of radius > 0.4km moons to be 600 (within a factor of 2).  At the faintest magnitudes we find a relatively shallow luminosity function of exponential index α = 0.29 ± 0.15, corresponding to a differential diameter power law of index q ≈ 2.5.
Primordial Stability of the Earth–Mars Belt
Authors: Huang Yukun , Gladman Brett
Published: October 2020

Previous work has demonstrated orbital stability for 100 Myr of initially near-circular and coplanar small bodies in a region termed the 'Earth–Mars belt' from 1.08 au
Martian Aquifers: Detection by Magnetic Sounding from Surface Magnetometry
Authors: Yu Yanan , Luhmann Janet , Russell Christopher
Published: October 2020

Magnetic pulsations are observed at Mars in the magnetotail and on the surface by the Maven and InSight magnetometers. The surface observations exhibit a frequency-dependent polarization in which the amplitude of the vertical component weakens with increasing frequency. This frequency dependence is not seen in the source regions studied by MAVEN. The source of the frequency dependence must be in the subsurface of Mars. The attenuation is consistent with an aquifer that is 3 km thick, containing water of the conductivity of terrestrial seawater.
Re-evaluation of Lunar X-ray observations by Apollo 15 &
Authors: Kuulkers Erik , Gloudemans Anniek
Published: October 2020

The Apollo 15 & 16 missions were the first to explore the Lunar surface chemistry by investigating about 10 percent of the Lunar surface using a remote sensing X-ray fluorescence spectrometer experiment. The data obtained has been extensively used to study Lunar formation history and geological evolution. In this work a re-evaluation of the Apollo 15 & 16 X-ray fluorescence experiment is conducted with the aim to obtain up-to-date empirical values for aluminum (Al) and magnesium (Mg) concentrations relative to silicon (Si) of the upper Lunar surface. An up-to-date orbit reconstruction, updated instrument response, and improved intensity ratio calculations are used to obtain new intensity ratio maps.
Flyby encounters between two planetary systems
Authors: Li Daohai , Mustill Alexander , Davies Melvyn
Published: October 2020

Stars born in clusters are subject to frequent stellar flybys and so are their planets. The influence of an encounter reaches beyond the brief flyby itself in that the mutual forcing between the planets will continue to shape the planetary system in the long term and in a way that is impossible without the encounter in the first place. As a consequence, different planetary systems of different orbital scales and mass ranges behave differently as a result of the encounters. Here we study the encounters between two planetary systems where each star has its own planets using N-body simulations. Besides the immediate effect of the encounter, we have also propagated the systems post-encounter for up to 10^8 yr. See Figure 1 for an illustration.We find that immediately during the encounter, a planet can be ejected from its original host star. Here, the interplanetary interactions are negligible and a planet’s stellar-centric distance is a key factor. Only encounters closer than a few times that distance can cause strong disturbances, e.g., to eject the planet or to break the resonance in multi-planet systems. This means that close-in (
Linking the formation and fate of exo-Kuiper belts within Solar system analogues
Authors: Veras Dimitri , Reichert Katja , Flammini Dotti Francesco , Cai Maxwell , Mustill Alexander , Shannon Andrew , McDonald Catriona , Portegies Zwart Simon , Kouwenhoven Mattheus , Spurzem Rainer
Published: October 2020

Escalating observations of exo-minor planets and their destroyed remnants both passing through the Solar system and within white dwarf planetary systems motivate an understanding of the orbital history and fate of exo-Kuiper belts and scattered discs. Here, we explore how the structure of a 40-1000 au annulus of bodies (comets, planetesimals, asteroids) orbiting inside of a Solar system analogue that is itself initially embedded within a stellar cluster environment varies as the star evolves through all of its stellar phases. We attempt this computationally challenging link in four parts: (1) by performing stellar cluster simulations lasting 100 Myr, (2) by making assumptions about the subsequent quiescent 11 Gyr main-sequence evolution, (3) by performing simulations throughout the giant branch phases of evolution, and (4) by making assumptions about the belt's evolution during the white dwarf phase. Throughout these stages, we estimate the planetesimals' gravitational responses to analogues of the four Solar system giant planets, as well as to collisional grinding, Galactic tides, stellar flybys, and stellar radiation. We find that the imprint of stellar cluster dynamics on the architecture of ≳100 km-sized exo-Kuiper belt planetesimals is retained throughout all phases of stellar evolution unless violent gravitational instabilities are triggered either (1) amongst the giant planets, or (2) due to a close (≪1000 au) stellar flyby. In the absence of these instabilities, these minor planets simply double their semimajor axis while retaining their primordial post-cluster eccentricity and inclination distributions, with implications for metal-polluted white dwarfs and the free-floating planetesimal population.Caption: Cartoon describing how we modelled exo-Kuiper belts through all stages of evolution with different numerical codes and forces.
D atmospheric modelling of K2-18b
Authors: Blain Doriann , Charnay Benjamin , Bézard Bruno
Published: October 2020

The atmospheric composition of exoplanets with masses between 2 and 10 M⊕ is poorly known. In that regard, the sub-Neptune K2-18b offers a valuable opportunity for the characterisation of such atmospheres under Earth-like stellar irradiation. Previous analyses of its transmission spectrum from the Kepler, Hubble and Spitzer space telescopes data using both retrieval algorithms and forward-modelling suggest the presence H2O, as well as a low amount of CH4 in a H2–He atmosphere.We present here simulations of the atmosphere of K2-18 b using Exo-REM, our self-consistent 1D atmospheric model — recently adapted for transiting, high-metallicity giant exoplanets — to study the atmosphere of K2-18b. We compared the transmission spectra computed by our model with the above-mentionned data (0.4 to 5 μm) to infer the planet atmospheric composition assuming a H2–He dominated atmosphere. We investigated the effect of irradiation, eddy diffusion coefficient, internal source, clouds, C/O ratio and metallicity on the atmospheric structure and transit spectrum. We will put an emphasis of the relative contributions of the various absorbers to the transmission spectrum. We will show that our simulations favor atmospheric metallicities from 100 to 200 times solar. We will also discuss the possibility of a CH4-depleted atmosphere and of liquid H2O cloud formation.
Anisotropy of long-period comets explained by their formation process
Authors: Higuchi Arika
Published: October 2020

Long-period comets coming from the Oort cloud are thought to be planetesimals formed in the planetary region on the ecliptic plane. We have investigated the orbital evolution of these bodies due to the Galactic tide. We extended Higuchi et al. (2007) and derived the analytical solutions to the Galactic longitude and latitude of the direction of aphelion, L and B. Using the analytical solutions, we show that the ratio of the periods of the evolution of L and B is very close to either 2 or ∞ for initial eccentricities ei∼1, as is true for the Oort cloud comets. From the relation between L and B, we predict that Oort cloud comets returning to the planetary region concentrate on the ecliptic plane and a second plane, which we call the "empty ecliptic". This consists in a rotation of 180° of the ecliptic around the Galactic pole. Our numerical integrations confirm that the radial component of the Galactic tide, which is neglected in the derivation of the analytical solutions, is not strong enough to break the relation between L and B derived analytically. Brief examination of observational data shows that there are concentrations near both the ecliptic and the empty ecliptic. We also show that the anomalies of the distribution of B of long-period comets mentioned by several authors are explained by the concentrations on the two planes more consistently than the previous explanation.
Wind of Change: Atmospheric wind retrieval and its implications for hot Jupiters
Authors: Seidel Julia , Ehrenreich David , Bourrier Vincent , Pino Lorenzo , Wyttenbach Aurelien , Allart Romain , Lavie Baptiste , Mounzer Dany , Lovis Christophe
Published: October 2020

The sodium doublet is one of the most powerful probes of exoplanet atmospheric properties when observed in transmission spectroscopy during transits. Recent high-spectral resolution observations of the sodium doublet in hot gas giants allowed us to resolve the line shape, opening the way for extracting atmospheric properties using line-profile fitting. Using the MERC code (Seidel et al. 2020a), a retrieval tool to determine temperature-pressure profiles and high-altitude winds in exoplanet thermospheres, we have studied the curiously broadened sodium signatures of various hot Jupiters. We have updated the MERC code to a quasi 3D treatment of the atmosphere (Seidel et al. 2020c, in prep.) and analysed three hot Jupiters, spanning a wide range of this class of exoplanets (see figure). Using the sodium signature of three examples - WASP-76b (a highly irradiated ultra-hot Jupiter, Seidel et al. 2019), KELT-11b (a puffy hot Jupiter, Mounzer et al. 2020, in prep.), and lastly HD189733b (one of the most studied hot Jupiters to date, Wyttenbach et al. 2015) - we explore possible trends in the atmospheric structure of hot Jupiters.We will first introduce the new quasi 3D retrieval of MERC, and proceed to show that high-velocity winds in the thermosphere are one possible explanation of the broadened sodium features seen in hot Jupiters. We plan to highlight various caveats and present likely origin scenarios for the observed wind patterns. We will then put these results in the context of past studies using global circulation models (GCMs) on hot Jupiters.
Momentum Enhancement Simulations for Hypervelocity Impacts on Sandstone
Authors: Chocron Sidney , Walker James , Grosch Donald , Beissel Stephen , Durda Daniel , Housen Kevin
Published: October 2020

Two NASA missions that will be launched in 2022 have spun renewed interest in hypervelocity impact of  rocks and metals. This work focuses on the prediction of the momentum enhancement effect, i.e. the extra momentum acquired by the target due to the ejecta flying off the target in the direction of the impactor. Predicting the momentum enhancement with simulations has been elusive, probably because the target material is rarely well characterized. This presentation shows that, given a good knowledge of the properties of the target material and, by adding two essential pieces of the physics (strength of failed material and bulking after failure), the computer simulations can provide good predictions of the momentum enhancement for hypervelocity impact tests performed at Southwest Research Institute.