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this paper reviews vlasov-based numerical methods used to model plasma in space physics and astrophysics. plasma consists of collectively behaving charged particles that form the major part of baryonic matter in the universe. many concepts ranging from our own planetary environment to the solar system and beyond can be... | vlasov methods in space physics and astrophysics |
we present the first application of a bin-scheme microphysical and vertical transport model to determine the size distribution of titanium and silicate cloud particles in the atmospheres of hot jupiters. we predict particle size distributions from first principles for a grid of planets at four representative equatorial... | formation of silicate and titanium clouds on hot jupiters |
transition disks with large dust cavities around young stars are promising targets for studying planet formation. previous studies have revealed the presence of gas cavities inside the dust cavities, hinting at recently formed, giant planets. however, many of these studies are biased toward the brightest disks in the n... | new insights into the nature of transition disks from a complete disk survey of the lupus star-forming region |
regional transport always plays a crucial role in the formation and dissipation of haze over the beijing-tianjin-hebei (bth) region. this study, conducted using pollution and meteorological observations and the weather research and forecasting model (wrf) coupled with the comprehensive air quality model with extensions... | multiple perspectives for modeling regional pm2.5 transport across cities in the beijing-tianjin-hebei region during haze episodes |
the seasonal variability of black carbon (bc) aerosols in india is studied using high resolution (10 km) bc simulations conducted using the weather research and forecasting model coupled with chemistry. the model reproduces the observed seasonality of surface bc fairly well over most parts of india but fails to capture... | what controls the seasonal cycle of black carbon aerosols in india? |
the growth of dust grains in protoplanetary disks is a necessary first step towards planet formation1. this growth has been inferred from observations of thermal dust emission2 towards mature protoplanetary systems (age >2 million years) with masses that are, on average, similar to neptune3. in contrast, the majorit... | evidence for the start of planet formation in a young circumstellar disk |
ribose is the central molecular subunit in rna, but the prebiotic origin of ribose remains unknown. we observed the formation of substantial quantities of ribose and a diversity of structurally related sugar molecules such as arabinose, xylose, and lyxose in the room-temperature organic residues of photo-processed inte... | ribose and related sugars from ultraviolet irradiation of interstellar ice analogs |
quantifying the atmospheric mass loss during planet formation is crucial for understanding the origin and evolution of planetary atmospheres. we examine the contributions to atmospheric loss from both giant impacts and planetesimal accretion. giant impacts cause global motion of the ground. using analytic self-similar ... | atmospheric mass loss during planet formation: the importance of planetesimal impacts |
mass-radius relationships for water-rich rocky planets are usually calculated assuming most water is present in condensed (either liquid or solid) form. planet density estimates are then compared to these mass-radius relationships, even when these planets are more irradiated than the runaway greenhouse irradiation limi... | revised mass-radius relationships for water-rich rocky planets more irradiated than the runaway greenhouse limit |
we present a combined observational and theoretical analysis to investigate the nature of plasma turbulence at kinetic scales in the earth’s magnetosheath. in the first decade of the kinetic range, just below the ion gyroscale, the turbulence was found to be similar to that in the upstream solar wind: predominantly ani... | nature of kinetic scale turbulence in the earth's magnetosheath |
the initial mass distribution in the solar nebula is a critical input to planet formation models that seek to reproduce today's solar system 1 . traditionally, constraints on the gas mass distribution are derived from observations of the dust emission from disks 2,3 , but this approach suffers from large uncertainties ... | mass inventory of the giant-planet formation zone in a solar nebula analogue |
the precursors to larger, biologically relevant molecules are detected throughout interstellar space, but determining the presence and properties of these molecules during planet formation requires observations of protoplanetary disks at high angular resolution and sensitivity. here, we present 0"3 observations of hc3n... | molecules with alma at planet-forming scales (maps). ix. distribution and properties of the large organic molecules hc3n, ch3cn, and c-c3h2 |
this chapter reviews accretion models for kuiper belt objects (kbos), discussing in particular the compatibility of the observed properties of the kbo population with the streaming instability paradigm. then it discusses how the dynamical structure of the kbo population, including the formation of its five subcomponent... | kuiper belt: formation and evolution |
we report helium absorption from the escaping atmosphere of toi 560.01 (hd 73583b), an r = 2.8r ⊕, p = 6.4 day mini-neptune orbiting a young (~600 myr) k dwarf. using keck/nirspec, we detect a signal with an average depth of 0.68% ± 0.08% in the line core. the absorption signal repeats during a partial transit obtained... | escaping helium from toi 560.01, a young mini-neptune |
we detect lyα absorption from the escaping atmosphere of hd 63433c, a r = 2.67r ⊕, p = 20.5 day mini-neptune orbiting a young (440 myr) solar analog in the ursa major moving group. using hubble space telescope (hst)/space telescope imaging spectrograph, we measure a transit depth of 11.1 ± 1.5% in the blue wing and 8 ±... | detection of ongoing mass loss from hd 63433c, a young mini-neptune |
stellar rotation periods are valuable both for constraining models of angular momentum loss and for understanding how magnetic features impact inferences of exoplanet parameters. building on our previous work in the northern hemisphere, we have used long-term, ground-based photometric monitoring from the mearth observa... | new rotation period measurements for m dwarfs in the southern hemisphere: an abundance of slowly rotating, fully convective stars |
active dark flows known as recurring slope lineae have been observed on the warmest slopes of equatorial mars. the morphology, composition and seasonality of the lineae suggest a role of liquid water in their formation. however, internal and atmospheric sources of water appear to be insufficient to sustain the observed... | formation of recurring slope lineae on mars by rarefied gas-triggered granular flows |
in the present work sensitivity of weather research forecasting (wrf) model has been carried out using five planetary boundary layer (pbl) schemes - yonsei university scheme (ysu), mellor-yamada-janjić scheme (myj), aymmetric convective model version 2 (acm2), quasi normal scale elimination scheme (qnse), mellor-yamada... | sensitivity of wrf model estimates to various pbl parameterizations in different climatic zones over india |
the planetary camera and spectrograph (pcs) for the extremely large telescope (elt) will be dedicated to detecting and characterising nearby exoplanets with sizes from sub-neptune to earth-size in the neighbourhood of the sun. this goal is achieved by a combination of extreme adaptive optics (xao), coronagraphy and spe... | pcs — a roadmap for exoearth imaging with the elt |
ex lup is a low-mass pre-main-sequence star that occasionally shows accretion-related outbursts. here, we present jwst/miri medium-resolution spectroscopy obtained for ex lup 14 yr after its powerful outburst. ex lup is now in quiescence and displays a class ii spectrum. we detect a forest of emission lines from molecu... | jwst/miri spectroscopy of the disk of the young eruptive star ex lup in quiescence |
mass-independent isotopic anomalies define two cosmochemically distinct regions: the carbonaceous and non-carbonaceous meteorites1, implying that the non-carbonaceous (terrestrial) and carbonaceous (jovian) reservoirs were kept separate during and after planet formation. the formation of jupiter is widely invoked to ex... | the partitioning of the inner and outer solar system by a structured protoplanetary disk |
with the discovery of planets beyond our solar system 25 years ago, exoplanet research has expanded dramatically, with new state-of-the-art ground-based and space-based missions dedicated to their discovery and characterisation. with more than 3,500 exoplanets now known, the complexity of the discovery techniques, obse... | the exoplanet handbook |
the transiting exoplanet survey satellite (tess) will provide high-precision time series photometry for millions of stars with at least a half-hour cadence. of particular interest are the circular regions of 12° radius centred around the ecliptic poles that will be observed continuously for a full year. spectroscopic s... | the tess-hermes survey data release 1: high-resolution spectroscopy of the tess southern continuous viewing zone |
the response of the indian summer monsoon (ism) circulation and precipitation to middle east dust aerosols on sub-seasonal timescales is studied using observations and the weather research and forecasting model coupled with online chemistry (wrf-chem). satellite data show that the ism rainfall in coastal southwest indi... | consistent response of indian summer monsoon to middle east dust in observations and simulations |
planetesimals may form from the gravitational collapse of dense particle clumps initiated by the streaming instability. we use simulations of aerodynamically coupled gas-particle mixtures to investigate whether the properties of planetesimals formed in this way depend upon the sizes of the particles that participate in... | evidence for universality in the initial planetesimal mass function |
this paper uses observations of dusty debris discs, including a growing number of gas detections in these systems, to test our understanding of the origin and evolution of this gaseous component. it is assumed that all debris discs with icy planetesimals create second generation co, c and o gas at some level, and the a... | predictions for the secondary co, c and o gas content of debris discs from the destruction of volatile-rich planetesimals |
radial substructures in circumstellar discs are now routinely observed by atacama large millimeter/submillimeter array. there is also growing evidence that disc winds drive accretion in such discs. we show through 2d (axisymmetric) simulations that rings and gaps develop naturally in magnetically coupled disc-wind syst... | the formation of rings and gaps in magnetically coupled disc-wind systems: ambipolar diffusion and reconnection |
the recent discovery of three earth-sized, potentially habitable planets around a nearby cool star, trappist-1, has provided three key targets for the upcoming james webb space telescope (jwst). depending on their atmospheric characteristics and precise orbit configurations, it is possible that any of the three planets... | habitable worlds with jwst: transit spectroscopy of the trappist-1 system? |
this paper presents the atmospheric characterization of three large, gaseous planets: wasp-127 b, wasp-79 b, and wasp-62 b. we analyzed spectroscopic data obtained with the g141 grism (1.088-1.68 μm) of the wide field camera 3 on board the hubble space telescope using the iraclis pipeline and the taurex3 retrieval code... | ares. ii. characterizing the hot jupiters wasp-127 b, wasp-79 b, and wasp-62b with the hubble space telescope |
solar coronal mass ejections (cmes) and flares have a statistically well-defined relationship, with more energetic x-ray flares corresponding to faster and more massive cmes. how this relationship extends to more magnetically active stars is a subject of open research. here we study the most probable stellar cme candid... | the stellar cme-flare relation: what do historic observations reveal? |
lakes existed on mars later than 3.6 billion years ago, according to sedimentary evidence for deltaic deposition. the observed fluviolacustrine deposits suggest that individual lake-forming climates persisted for at least several thousand years (assuming dilute flow). but the lake watersheds’ little-weathered soils ind... | methane bursts as a trigger for intermittent lake-forming climates on post-noachian mars |
exoplanet catalogs produced by surveys suffer from a lack of completeness (not every planet is detected) and less than perfect reliability (not every planet in the catalog is a true planet), particularly near the survey's detection limit. exoplanet occurrence rate studies based on such a catalog must be corrected for c... | a probabilistic approach to kepler completeness and reliability for exoplanet occurrence rates |
the final architecture of planetary systems depends on the extraction of angular momentum and mass-loss processes of the discs in which they form. theoretical studies proposed that magnetohydrodynamic winds launched from the discs (mhd disc winds) could govern accretion and disc dispersal. in this work, we revisit the ... | mhd disc winds can reproduce fast disc dispersal and the correlation between accretion rate and disc mass in lupus |
we present stellar rotation periods for late k- and early m-dwarf members of the 4 gyr old open cluster m67 as calibrators for gyrochronology and tests of stellar spin-down models. using gaia edr3 astrometry for cluster membership and pan-starrs (ps1) photometry for binary identification, we build this set of rotation ... | a 4 gyr m-dwarf gyrochrone from cfht/megaprime monitoring of the open cluster m67 |
water, the most abundant volatile in earth’s interior, preserves the young surface of our planet by catalysing mantle convection, lubricating plate tectonics and feeding arc volcanism. since planetary accretion, water has been exchanged between the hydrosphere and the geosphere, but its depth distribution in the mantle... | upper-mantle water stratification inferred from observations of the 2012 indian ocean earthquake |
recent measurements of the volatile composition of the coma of comet 67p/churyumov-gerasimenko (hereafter 67p) allow constraints to be set on the origin of volatile elements (water, carbon, nitrogen, noble gases) in inner planets' atmospheres. analyses by the rosina mass spectrometry system onboard the rosetta spacecra... | origins of volatile elements (h, c, n, noble gases) on earth and mars in light of recent results from the rosetta cometary mission |
in this work we investigate the impact of calculating non-equilibrium chemical abundances consistently with the temperature structure for the atmospheres of highly-irradiated, close-in gas giant exoplanets. chemical kinetics models have been widely used in the literature to investigate the chemical compositions of hot ... | the effects of consistent chemical kinetics calculations on the pressure-temperature profiles and emission spectra of hot jupiters |
we combine analytical understanding of resonant dynamics in two-planet systems with machine-learning techniques to train a model capable of robustly classifying stability in compact multiplanet systems over long timescales of 109 orbits. our stability of planetary orbital configurations klassifier (spock) predicts stab... | predicting the long-term stability of compact multiplanet systems |
the galilean moons play major roles in the giant magnetosphere of jupiter. at the same time, the magnetospheric particles and fields affect the moons. the impact of magnetospheric ions on the moons' atmospheres supplies clouds of escaping neutral atoms that populate a substantial fraction of their orbits. at the same t... | the space environment of io and europa |
anthropogenic heat (ah) emissions from human activities caused by urbanization can affect the city environment. based on the energy consumption and the gridded demographic data, the spatial distribution of ah emission over the yangtze river delta (yrd) region is estimated. meanwhile, a new method for the ah parameteriz... | modeling of the anthropogenic heat flux and its effect on regional meteorology and air quality over the yangtze river delta region, china |
during recent winters, hazes often occurred in beijing, causing major environmental problems. to understand the causes of this "beijing haze", a haze episode (from oct. 21 to oct. 31, 2013) in beijing was analyzed. during the episode, the daily mean concentration of fine particulate matter (pm2.5) reached a peak value ... | a budget analysis of the formation of haze in beijing |
we present exo-transmit, a software package to calculate exoplanet transmission spectra for planets of varied composition. the code is designed to generate spectra of planets with a wide range of atmospheric composition, temperature, surface gravity, and size, and is therefore applicable to exoplanets ranging in mass a... | exo-transmit: an open-source code for calculating transmission spectra for exoplanet atmospheres of varied composition |
earth's climate, mantle, and core interact over geologic time scales. climate influences whether plate tectonics can take place on a planet, with cool climates being favorable for plate tectonics because they enhance stresses in the lithosphere, suppress plate boundary annealing, and promote hydration and weakening of ... | whole planet coupling between climate, mantle, and core: implications for rocky planet evolution |
southern west greenland contains some of the best-studied and best-preserved magmatic eoarchean rocks on earth, and these provide an excellent vantage point from which to view long-standing questions regarding the growth of the earliest continental crust. in order to address the questions surrounding early crustal grow... | using the magmatic record to constrain the growth of continental crust-the eoarchean zircon hf record of greenland |
this book on multiscale seismic tomography, written by one of the leaders in the field, is suitable for undergraduate and graduate students, researchers, and professionals in earth and planetary sciences who need to broaden their horizons about seismotectonics, volcanism, and interior structure and dynamics of the eart... | multiscale seismic tomography |
we present results from a quantitative spectroscopic analysis conducted on archival keck/hires high-resolution spectra from the california-kepler survey (cks) sample of transiting planetary host stars identified from the kepler mission. the spectroscopic analysis was based on a carefully selected set of fe i and fe ii ... | a spectroscopic analysis of the california-kepler survey sample. i. stellar parameters, planetary radii, and a slope in the radius gap |
theoretical models of stellar evolution predict that most of the lithium inside a star is destroyed as the star becomes a red giant. however, observations reveal that about 1% of red giants are peculiarly rich in lithium, often exceeding the amount in the interstellar medium or predicted from the big bang. with only ab... | tidal interactions between binary stars can drive lithium production in low-mass red giants |
evidence of star-planet interactions in the form of planet-modulated chromospheric emission has been noted for a number of hot jupiters. magnetic star-planet interactions involve the release of energy stored in the stellar and planetary magnetic fields. these signals thus offer indirect detections of exoplanetary magne... | magnetic field strengths of hot jupiters from signals of star-planet interactions |
the prevalence of substructures in ∼1-10 myr old protoplanetary disks, which are often linked to planet formation, has raised the question of how early such features form and, as a corollary, how early planet formation begins. here we present observations of seven protostellar disks (aged ∼ 0.1-1 myr) from the very lar... | the vla/alma nascent disk and multiplicity (vandam) survey of orion protostars. iii. substructures in protostellar disks |
we performed a stereo-photogrammetric (spg) analysis of more than 1500 rosetta/osiris nac images of comet 67p/churyumov-gerasimenko (67p). the images with pixel scales in the range 0.2-3.0 m/pixel were acquired between august 2014 and february 2016. we finally derived a global high-resolution 3d description of 67p's su... | the global meter-level shape model of comet 67p/churyumov-gerasimenko |
james webb space telescope (jwst) transmission and emission spectra will provide invaluable glimpses of transiting exoplanet atmospheres, including possible biosignatures. this promising science from jwst, however, will require exquisite precision and understanding of systematic errors that can impact the time series o... | jwst noise floor. i. random error sources in jwst nircam time series |
magnetic flux ropes are characterized by coherently twisted magnetic field lines, which are ubiquitous in magnetized plasmas. as the core structure of various eruptive phenomena in the solar atmosphere, flux ropes hold the key to understanding the physical mechanisms of solar eruptions, which impact the heliosphere and... | magnetic flux ropes in the solar corona: structure and evolution toward eruption |
we present the discovery and characterisation of two transiting planets observed by the transiting exoplanet survey satellite (tess) orbiting the nearby (d⋆ ≈ 22 pc), bright (j ≈ 9 mag) m3.5 dwarf ltt 3780 (toi-732). we confirm both planets and their association with ltt 3780 via ground-based photometry and determine t... | the carmenes search for exoplanets around m dwarfs. two planets on opposite sides of the radius gap transiting the nearby m dwarf ltt 3780 |
we introduce zeus, a well-tested python implementation of the ensemble slice sampling (ess) method for bayesian parameter inference. ess is a novel markov chain monte carlo (mcmc) algorithm specifically designed to tackle the computational challenges posed by modern astronomical and cosmological analyses. in particular... | zeus: a python implementation of ensemble slice sampling for efficient bayesian parameter inference |
we present results from a set of simulations using a fully coupled three-dimensional (3d) chemistry-radiation-hydrodynamics model and investigate the effect of transport of chemical species by the large-scale atmospheric flow in hot jupiter atmospheres. we coupled a flexible chemical kinetics scheme to the met office u... | implications of three-dimensional chemical transport in hot jupiter atmospheres: results from a consistently coupled chemistry-radiation-hydrodynamics model |
the kepler mission revealed a class of planets known as "super-puffs," with masses only a few times larger than earth's but radii larger than neptune, giving them very low mean densities. all three of the known planets orbiting the young solar-type star kepler 51 are super-puffs. the kepler 51 system thereby provides a... | the featureless transmission spectra of two super-puff planets |
the young massive jupiters discovered with high-contrast imaging1-4 provide a unique opportunity to study the formation and early evolution of gas giant planets. a key question is to what extent gravitational energy from accreted gas contributes to the internal energy of a newly formed planet. this has led to a range o... | the mass of the young planet beta pictoris b through the astrometric motion of its host star |
organic compounds occur in some chondritic meteorites, and their signatures on solar system bodies have been sought for decades. spectral signatures of organics have not been unambiguously identified on the surfaces of asteroids, whereas they have been detected on cometary nuclei. data returned by the visible and infra... | localized aliphatic organic material on the surface of ceres |
we present observations by the mars atmosphere and volatile evolution (maven) mission of a substantial plume-like distribution of escaping ions from the martian atmosphere, organized by the upstream solar wind convection electric field. from a case study of maven particle-and-field data during one spacecraft orbit, we ... | strong plume fluxes at mars observed by maven: an important planetary ion escape channel |
the design and construction of carmenes has been presented at previous spie conferences. it is a next-generation radial-velocity instrument at the 3.5m telescope of the calar alto observatory, which was built by a consortium of eleven spanish and german institutions. carmenes consists of two separate échelle spectrogra... | carmenes: high-resolution spectra and precise radial velocities in the red and infrared |
the perihelion of mercury’s orbit precesses due to perturbations from other solar system bodies, solar quadrupole moment (j 2), and relativistic gravitational effects that are proportional to linear combinations of the parametrized post-newtonian parameters β and γ. the orbits and masses of the solar system bodies are ... | precession of mercury’s perihelion from ranging to the messenger spacecraft |
au mic is a young planetary system with a resolved debris disc showing signs of planet formation and two transiting warm neptunes near mean-motion resonances. here we analyse three transits of au mic b observed with the characterising exoplanet satellite (cheops), supplemented with sector 1 and 27 transiting exoplanet ... | the changing face of au mic b: stellar spots, spin-orbit commensurability, and transit timing variations as seen by cheops and tess |
this paper describes the 2020 release of the geisa database (gestion et etude des informations spectroscopiques atmosphériques: management and study of atmospheric spectroscopic information), developed and maintained at lmd since 1974. geisa is the reference database for several current or planned thermal and short-wav... | the 2020 edition of the geisa spectroscopic database |
observations of exoplanet atmospheres have shown that aerosols, like in the solar system, are common across a variety of temperatures and planet types. the formation and distribution of these aerosols are inextricably intertwined with the composition and thermal structure of the atmosphere. at the same time, these aero... | aerosols in exoplanet atmospheres |
we present the most detailed data-driven exploration of cloud opacity in a substellar object to-date. we have tested over 60 combinations of cloud composition and structure, particle-size distribution, scattering model, and gas phase composition assumptions against archival 1-15 μm spectroscopy for the unusually red l4... | cloud busting: enstatite and quartz clouds in the atmosphere of 2m2224-0158 |
determining whether plate tectonics or some other mode of planetary dynamics operated in the early archean is one of the most contentious and debated areas of earth sciences today. the paleo- mesoarchean dome-and-basin structures of the eastern pilbara craton are widely used as an example of an early archean terrane su... | archean dome-and-basin style structures form during growth and death of intraoceanic and continental margin arcs in accretionary orogens |
double planetary gear sets (dpgss) are widely applied to high power and high torque mechanical transmission systems due to the high loading capacity, steady transmission, and high transmission efficiency. most previous works studied the planetary bearing vibration characteristics without the gear excitations. this work... | a dynamic model for the planetary bearings in a double planetary gear set |
static compression experiments over 4 mbar are rare, yet critical for developing accurate fundamental physics and chemistry models, relevant to a range of topics including modeling planetary interiors. here we show that focused ion beam crafted toroidal single-crystal diamond anvils with 9.0 μm culets are capable of pr... | single crystal toroidal diamond anvils for high pressure experiments beyond 5 megabar |
the university of california, san diego (ucsd) time-dependent three-dimensional (3-d) reconstruction technique provides volumetric maps of density, velocity, and solar surface extrapolated magnetic fields by iteratively fitting our kinematic 3-d model to interplanetary scintillation (ips) observations. while we current... | interplanetary scintillation (ips) analyses during lofar campaign mode periods that include the first three parker solar probe close passes of the sun |
the dynamical and thermodynamical importance of gravity waves was initially recognized in the atmosphere of earth. extensive studies over recent decades demonstrated that gravity waves exist in atmospheres of other planets, similarly play a significant role in the vertical coupling of atmospheric layers and, thus, must... | gravity waves in planetary atmospheres: their effects and parameterization in global circulation models |
we use the robo-ao survey of kepler planetary candidate host stars, the largest adaptive optics survey yet performed, to measure the recovery rate of close stellar binaries in gaia dr2. we find that gaia recovers binaries down to 1″ at magnitude contrasts as large as six; closer systems are not resolved, regardless of ... | measuring the recoverability of close binaries in gaia dr2 with the robo-ao kepler survey |
the zinc (zn) stable isotope system has great potential for tracing planetary formation and differentiation processes due to its chalcophile, lithophile and moderately volatile character. as an initial approach, the terrestrial mantle, and by inference, the bulk silicate earth (bse), have previously been suggested to h... | zinc isotope fractionation during mantle melting and constraints on the zn isotope composition of earth's upper mantle |
outflows driven by large-scale magnetic fields likely play an important role in the evolution and dispersal of protoplanetary disks and in setting the conditions for planet formation. we extend our 2d-axisymmetric nonideal mhd model of these outflows by incorporating radiative transfer and simplified thermochemistry, w... | global hydromagnetic simulations of protoplanetary disks with stellar irradiation and simplified thermochemistry |
a stunning range of substructures in the dust of protoplanetary disks is routinely observed across a range of wavelengths. these gaps, rings and spirals are highly indicative of a population of unseen planets, hinting at the possibility of current observational facilities being able to capture planet-formation in actio... | visualizing the kinematics of planet formation |
thermal protection systems are a critical component of planetary exploration, enabling probes to enter the atmosphere and perform in-situ measurements. the aero-thermal conditions encountered during entry are destination and vehicle dependent, ranging from relatively benign conditions at mars and titan, to extreme cond... | thermal protection system requirements for future planetary entry and aerocapture missions |
in this proceedings, we study the possible gravitational impact of primordial black holes (pbhs) or dark matter (dm) clumps on gnss satellite orbits and gravimeter measurements. it provides a preliminary step to the future exhaustive statistical analysis over 28 years of gravimeter and gnss data to get constraints over... | observing dark matter clumps and asteroid-mass primordial black holes in the solar system with gravimeters and gnss networks |
we determine the observability in transmission of inhomogeneous cloud cover on the limbs of hot jupiters through post-processing a general circulation model to include cloud distributions computed using a cloud microphysics model. we find that both the east and west limbs often form clouds, but that the different prope... | transit signatures of inhomogeneous clouds on hot jupiters: insights from microphysical cloud modeling |
to determine the origin of the spiral structure observed in the dust continuum emission of elias 2-27 we analyze multiwavelength continuum alma data with a resolution of ~0"2 (~23 au) at 0.89, 1.3, and 3.3 mm. we also study the kinematics of the disk with 13co and c18o alma observations in the j = 3-2 transition. the s... | spiral arms and a massive dust disk with non-keplerian kinematics: possible evidence for gravitational instability in the disk of elias 2-27 |
following paper i we investigate the properties of atmospheres that form around small protoplanets embedded in a protoplanetary disc by conducting hydrodynamical simulations. these are now extended to three dimensions, employing a spherical grid centred on the planet. compression of gas is shown to reduce rotational mo... | hydrodynamics of embedded planets' first atmospheres - ii. a rapid recycling of atmospheric gas |
constraining turbulence in disks is key towards understanding their evolution through the transport of angular momentum. until now measurements of high turbulence have remained elusive and methods for estimating turbulence relay mostly on complex radiative transfer models of the data. using the disk emission from im lu... | high turbulence in the im lup protoplanetary disk: direct observational constraints from cn and c$_2$h emission |
the metallicity of exoplanet systems serves as a critical diagnostic of planet formation mechanisms. previous studies have demonstrated the planet-metallicity correlation for large planets ({{r}p} ≥slant 4 {{r}e}); however, a correlation has not been found for smaller planets. with a sample of 406 kepler objects of int... | revealing a universal planet-metallicity correlation for planets of different sizes around solar-type stars |
this work describes the update of no along with the incorporation of no2 and n2o to the hitemp database. where appropriate, the hitran line lists for the same molecules have also been updated. this work brings the current number of molecules provided by hitemp to seven. the initial line lists originating from ab initio... | spectroscopic line parameters of no, no2, and n2o for the hitemp database |
a primary goal of exoplanet characterization is to use a planet's current composition to understand how that planet formed. for example, the c/o ratio has long been recognized as carrying important information on the chemistry of volatile species. refractory elements, like fe, mg, and si, are usually not considered in ... | a new window into planet formation and migration: refractory-to-volatile elemental ratios in ultra-hot jupiters |
we investigate possible chemical conditions on a canonical hycean world, focusing on the present and primordial molecular composition of the atmosphere, and the inventory of bioessential elements for the origin and sustenance of life in the ocean. traditionally, the search for life on exoplanets has been predominantly ... | chemical conditions on hycean worlds |
in this paper, we study how gaseous dynamical friction (df) affects the motion of fly-by stellar-mass black holes (sbhs) embedded in active galactic nucleus (agn) discs. we perform three-body integrations of the interaction of two co-planar sbhs in nearby, initially circular orbits around the supermassive black hole. w... | gas dynamical friction as a binary formation mechanism in agn discs |
aerocapture is a maneuver which uses aerodynamic drag to slow down a spacecraft in a single pass through the atmosphere. all planetary orbiters to date have used propulsive orbit insertion. aerocapture is a promising alternative, especially for small satellite missions and missions to the ice giants. the large {\delta}... | performance benefit of aerocapture for the design reference mission set |
thanks to the muse integral field spectrograph on the vlt, extragalactic distance measurements with the [o iii] 5007 a planetary nebula luminosity function (pnlf) are now possible out to approx. 40 mpc. here we analyze the vlt/muse data for 20 galaxies from the eso public archive to identify the systems' planetary nebu... | towards precision cosmology with improved pnlf distances using vlt-muse ii. a test sample from archival data |
the activity of the sun alternates between a solar minimum and a solar maximum, the former corresponding to a period of "quieter" status of the heliosphere. during solar minimum, it is in principle more straightforward to follow eruptive events and solar wind structures from their birth at the sun throughout their inte... | cme evolution in the structured heliosphere and effects at earth and mars during solar minimum |
while dust disks around optically visible, class ii protostars are found to be vertically thin, when and how dust settles to the midplane are unclear. as part of the atacama large millimeter/submillimeter array large program, early planet formation in embedded disks, we analyze the edge-on, embedded, class i protostar ... | early planet formation in embedded disks (edisk). ii. limited dust settling and prominent snow surfaces in the edge-on class i disk iras 04302+2247 |
antarctic snowfall consists of frequent clear-sky precipitation and heavier falls from intrusions of maritime airmasses associated with amplified planetary waves. we investigate the importance of different precipitation events using the output of the racmo2 model. extreme precipitation events consisting of the largest ... | the dominant role of extreme precipitation events in antarctic snowfall variability |
the chemical composition of stars hosting small exoplanets (with radii less than four earth radii) appears to be more diverse than that of gas-giant hosts, which tend to be metal-rich. this implies that small, including earth-size, planets may have readily formed at earlier epochs in the universe's history when metals ... | an ancient extrasolar system with five sub-earth-size planets |
the admitted, conventional scenario to explain the complex spectral evolution of brown dwarfs (bds) since their first detection 20 years ago has always been the key role played by micron-size condensates, called “dust” or “clouds,” in their atmosphere. this scenario, however, faces major problems, in particular the j-b... | cloudless atmospheres for l/t dwarfs and extrasolar giant planets |
the sun is the only star whose surface can be directly resolved at high resolution, and therefore constitutes an excellent test case to explore the physical origin of stellar radial-velocity (rv) variability. we present harps observations of sunlight scattered off the bright asteroid 4/vesta, from which we deduced the ... | the sun as a planet-host star: proxies from sdo images for harps radial-velocity variations |
we report the detection of water absorption features in the day side spectrum of the first-known hot jupiter, 51 peg b, confirming the star-planet system to be a double-lined spectroscopic binary. we use high-resolution (r≈ 100,000), 3.2 μ {{m}} spectra taken with crires/vlt to trace the radial-velocity shift of the wa... | discovery of water at high spectral resolution in the atmosphere of 51 peg b |
we carried out a systematic study of full-orbit phase curves for known transiting systems in the northern ecliptic sky that were observed during year 2 of the tess primary mission. we applied the same methodology for target selection, data processing, and light-curve fitting as we did in our year 1 study. out of the 15... | visible-light phase curves from the second year of the tess primary mission |
binary evolution theory predicts that the second common envelope (ce) ejection can produce low-mass (0.32-0.36 msun) subdwarf b (sdb) stars inside ultrashort-orbital-period binary systems, as their helium cores are ignited under nondegenerate conditions. with the orbital decay driven by gravitational-wave (gw) radiatio... | a seven-earth-radius helium-burning star inside a 20.5-min detached binary |
the samarium-146 (146sm)-neodymium-142 (142nd) short-lived decay system (half-life of 103 million years) is a powerful tracer of the early mantle-crust evolution of planetary bodies. however, an increased 142nd/144nd in modern terrestrial rocks relative to chondrite meteorites has been proposed to be caused by nucleosy... | earth’s composition was modified by collisional erosion |
life on planet earth is under siege. we are now in an uncharted territory. for several decades, scientists have consistently warned of a future marked by extreme climatic conditions because of escalating global temperatures caused by ongoing human activities that release harmful greenhouse gasses into the atmosphere. u... | the 2023 state of the climate report: entering uncharted territory |
massive and water-rich planets should be ubiquitous in the universe. many of these worlds are expected to be subject to important irradiation from their host star, and display supercritical water layers surrounded by extended steam atmospheres. irradiated ocean planets with such inflated hydrospheres have been recently... | mass-radius relationships for irradiated ocean planets |
palatini f(r) gravity is probably the simplest extension of general relativity (gr) and the simplest realization of a metric-affine theory. it has the same number of degrees of freedom as gr and, in vacuum, it is straightforwardly mapped into gr with a cosmological constant. the mapping between gr and palatini f(r) ins... | palatini f(r) gravity tests in weak field limit: solar system, seismology and galaxies |
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