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self-sustained convective dynamos in planetary systems operate in an asymptotic regime of rapid rotation, where a balance is thought to hold between the coriolis, pressure, buoyancy and lorentz forces (the mac balance). classical numerical solutions have previously been obtained in a regime of moderate rotation where v... | spherical convective dynamos in the rapidly rotating asymptotic regime |
constraining planet formation based on the atmospheric composition of exoplanets is a fundamental goal of the exoplanet community. existing studies commonly try to constrain atmospheric abundances, or to analyze what abundance patterns a given description of planet formation predicts. however, there is also a pressing ... | interpreting the atmospheric composition of exoplanets: sensitivity to planet formation assumptions |
quantum mechanics governs the microscopic world, where low mass and momentum reveal a natural wave-particle duality. magnifying quantum behaviour to macroscopic scales is a major strength of the technique of cooling and trapping atomic gases, in which low momentum is engineered through extremely low temperatures. advan... | observation of bose-einstein condensates in an earth-orbiting research lab |
several properties of the solar system, including the wide radial spacing of the giant planets, can be explained if planets radially migrated by exchanging orbital energy and momentum with outer disk planetesimals. neptune's planetesimal-driven migration, in particular, has a strong advocate in the dynamical structure ... | dynamical evolution of the early solar system |
studies of the dwarf planet (1) ceres using ground-based and orbiting telescopes have concluded that its closest meteoritic analogues are the volatile-rich ci and cm carbonaceous chondrites. water in clay minerals, ammoniated phyllosilicates, or a mixture of mg(oh)2 (brucite), mg2co3 and iron-rich serpentine have all b... | ammoniated phyllosilicates with a likely outer solar system origin on (1) ceres |
the streaming instability (si) is a mechanism to aerodynamically concentrate solids in protoplanetary disks and trigger the formation of planetesimals. the si produces strong particle clumping if the ratio of solid to gas surface density-an effective metallicity-exceeds a critical value. this critical value depends on ... | thresholds for particle clumping by the streaming instability |
the "spice" system has been widely used since the days of the magellan mission to venus as the method for scientists and engineers to access a variety of space mission geometry such as positions, velocities, directions, orientations, sizes and shapes, and field-of-view projections (acton, 1996). while originally focuse... | a look towards the future in the handling of space science mission geometry |
amphibole (amp) plays a crucial role in the study of several earth and planetary processes. one of its most common applications is in thermobarometry, especially for volcanic-magmatic systems. however, many thermobarometers require the input of melt composition, which is not always available in volcanic products (e.g.,... | amp-tb2: an updated model for calcic amphibole thermobarometry |
earth’s geological history is divided into chronostratigraphic units that distinguish phases in the planet’s evolution by summarizing complex biotic, geochemical, and climatic changes. over the past century, many components of the earth system have changed so much that they no longer occur within the ranges evident dur... | defining the onset of the anthropocene |
aerocapture is a technique which uses atmospheric drag to decelerate a spacecraft and achieve nearly fuel-free orbit insertion from an interplanetary trajectory. the present study performs a historical review of the field, and a bibliometric data analysis of the literature from 1980 to 2023. the data offers insights in... | aerocapture: a historical review and bibliometric data analysis from 1980 to 2023 |
the interactions of electromagnetic radiation with ice, and with ice-containing media such as snow and clouds, are determined by the refractive index and absorption coefficient (the `optical constants') of pure ice as functions of wavelength. bulk reflectance, absorptance and transmittance are further influenced by gra... | optical properties of ice and snow |
smallholder farming is the most prevalent form of agriculture in the world, supports many of the planet’s most vulnerable populations, and coexists with some of its most diverse and threatened landscapes. however, there is little information about the location of small farms, making it difficult both to estimate their ... | subnational distribution of average farm size and smallholder contributions to global food production |
we assess the literature on innovation and upscaling for negative emissions technologies (nets) using a systematic and reproducible literature coding procedure. to structure our review, we employ the framework of sequential stages in the innovation process, with which we code each nets article in innovation space. we f... | negative emissions—part 3: innovation and upscaling |
knowledge of irrigation is essential for ensuring food and water security, and to cope with the scarcity of water resources, which is expected to exacerbate under the pressure of climate change and population increase. even though irrigation is likely the most important direct human intervention in the hydrological cyc... | how much water is used for irrigation? a new approach exploiting coarse resolution satellite soil moisture products |
in order to test accretion simulations as well as planetary differentiation scenarios, we have integrated a multistage core-mantle differentiation model with n-body accretion simulations. impacts between embryos and planetesimals are considered to result in magma ocean formation and episodes of core formation. the core... | accretion and differentiation of the terrestrial planets with implications for the compositions of early-formed solar system bodies and accretion of water |
land degradation has become one of the biggest environmental challenges human society is currently facing, which is why understanding the global pattern of this land crisis is absolutely necessary. however, so far, the multiple forms of this environmental issue have mainly been analysed in international scientific lite... | exploring the multiple land degradation pathways across the planet |
weather and climate models approximate diabatic and sub-grid-scale processes in terms of grid-scale variables using parameterizations. current parameterizations are designed by humans based on physical understanding, observations, and process modeling. as a result, they are numerically efficient and interpretable, but ... | prognostic validation of a neural network unified physics parameterization |
four extreme haze episodes occurred in october 2014 in the north china plain (ncp). to clarify the formation mechanism of hazes in autumn, strengthened observations were conducted in beijing from 5 october to 2 november. the meteorological parameters, satellite data, chemical compositions and optical properties of aero... | characteristics and formation mechanism of continuous hazes in china: a case study during the autumn of 2014 in the north china plain |
the formation of planetesimals is expected to occur via particle-gas instabilities that concentrate dust into self-gravitating clumps1-3. triggering these instabilities requires the prior pile-up of dust in the protoplanetary disk4,5. this has been successfully modelled exclusively at the disk's snowline6-9, whereas ro... | contemporary formation of early solar system planetesimals at two distinct radial locations |
there is growing evidence that microplastic pollution (<5 mm in size) is now present in virtually all marine ecosystems, even in remote areas, such as the arctic and the antarctic. microplastics have been found in water and sediments of the antarctic but little is known of their ingestion by higher predators and mec... | microplastics in gentoo penguins from the antarctic region |
we present a comprehensive evolutionary model of the sun’s protoplanetary disk, constructed to resolve the “cai storage problem” of meteoritics. we predict the abundances of calcium-rich, aluminum-rich inclusions (cais) and refractory lithophile elements under the central assumption that jupiter’s ∼30 m ⊕ core formed a... | the effect of jupiter's formation on the distribution of refractory elements and inclusions in meteorites |
the earth as a planetary system has experienced significant change since its formation c. 4.54 gyr ago. some of these changes have been gradual, such as secular cooling of the mantle, and some have been abrupt, such as the rapid increase in free oxygen in the atmosphere at the archean-proterozoic transition. many of th... | secular change and the onset of plate tectonics on earth |
this article describes the latest stable release (version 2.2) of the atmospheric radiative transfer simulator (arts), a public domain software for radiative transfer simulations in the thermal spectral range (microwave to infrared). the main feature of this release is a planetary toolbox that allows simulations for th... | arts, the atmospheric radiative transfer simulator - version 2.2, the planetary toolbox edition |
heavy air pollution is strongly influenced by weather conditions and is thus sensitive to climate change. especially, for the areas with complex topography such as the sichuan basin (sb), one of the most polluted areas of china, the synergistic effects of synoptic weather patterns and topography on air quality are uncl... | synergistic effects of synoptic weather patterns and topography on air quality: a case of the sichuan basin of china |
the depth to which jupiter’s observed east-west jet streams extend has been a long-standing question. resolving this puzzle has been a primary goal for the juno spacecraft, which has been in orbit around the gas giant since july 2016. juno’s gravitational measurements have revealed that jupiter’s gravitational field is... | jupiter’s atmospheric jet streams extend thousands of kilometres deep |
seasonal spatial and temporal gradients for the co2 mole fraction over north america are examined by creating a climatology from data collected 2004-2013 by the noaa/esrl global greenhouse gas reference network aircraft program relative to trends observed for co2 at the mauna loa observatory. the data analyzed are from... | seasonal climatology of co2 across north america from aircraft measurements in the noaa/esrl global greenhouse gas reference network |
the nasa double asteroid redirection test (dart) mission performed a kinetic impact on asteroid dimorphos, the satellite of the binary asteroid (65803) didymos, at 23:14 utc on 26 september 2022 as a planetary defence test1. dart was the first hypervelocity impact experiment on an asteroid at size and velocity scales r... | momentum transfer from the dart mission kinetic impact on asteroid dimorphos |
the debiased absolute-magnitude and orbit distributions as well as source regions for near-earth objects (neos) provide a fundamental frame of reference for studies of individual neos and more complex population-level questions. we present a new four-dimensional model of the neo population that describes debiased stead... | debiased orbit and absolute-magnitude distributions for near-earth objects |
many systems on our planet shift abruptly and irreversibly from the desired state to an undesired state when forced across a "tipping point". some examples are mass extinctions within ecosystems, cascading failures in infrastructure systems, and changes in human and animal social networks. the ability to avoid such reg... | network resilience |
solar geoengineering (sg) has the potential to restore average surface temperatures by increasing planetary albedo1-4, but this could reduce precipitation5-7. thus, although sg might reduce globally aggregated risks, it may increase climate risks for some regions8-10. here, using the high-resolution forecast-oriented l... | halving warming with idealized solar geoengineering moderates key climate hazards |
high-frequency gravitational waves (hfgws) carry a wealth of information on the early universe with a tiny comoving hubble horizon and astronomical objects of small scale but with dense energy. we demonstrate that the nearby planets, such as earth and jupiter, can be utilized as a laboratory for detecting the hfgws. th... | detecting high-frequency gravitational waves in planetary magnetosphere |
the molecules with alma at planet-forming scales large program (maps lp) surveyed the chemical structures of five protoplanetary disks across more than 40 different spectral lines at high angular resolution (0"15 and 0"30 beams for bands 6 and 3, respectively) and sensitivity (spanning 0.3-1.3 mjy beam-1 and 0.4-1.9 mj... | molecules with alma at planet-forming scales (maps). ii. clean strategies for synthesizing images of molecular line emission in protoplanetary disks |
aims: we aim to study vertical settling and radial drift of dust in protoplanetary disks from a different perspective: an edge-on view. an estimation of the amplitude of settling and drift is highly relevant to understanding planet formation.methods: we analyze a sample of 12 hst-selected edge-on protoplanetary disks (... | observations of edge-on protoplanetary disks with alma. i. results from continuum data |
a few studies have reported a significant dearth of exoplanets with neptune mass and radius with orbital periods below 2-4 d. this cannot be explained by observational biases because many neptunian planets with longer orbital periods have been detected. the existence of this desert is similar to the appearance of the s... | dearth of short-period neptunian exoplanets: a desert in period-mass and period-radius planes |
we present thermal phase curve measurements for the hot jupiter wasp-103b observed with hubble/wfc3 and spitzer/irac. the phase curves have large amplitudes and negligible hotspot offsets, indicative of poor heat redistribution to the nightside. we fit the phase variation with a range of climate maps and find that a sp... | global climate and atmospheric composition of the ultra-hot jupiter wasp-103b from hst and spitzer phase curve observations |
we derive analytic, closed-form solutions for the light curve of a planet transiting a star with a limb-darkening profile that is a polynomial function of the stellar elevation, up to an arbitrary integer order. we provide improved analytic expressions for the uniform, linear, and quadratic limb-darkened cases, as well... | analytic planetary transit light curves and derivatives for stars with polynomial limb darkening |
the best constraints on the internal structures of giant planets have historically originated from measurements of their gravity fields1-3. these data are inherently mostly sensitive to a planet's outer regions, stymieing efforts to measure the mass and compactness of the cores of jupiter2,4,5 and saturn6,7. however, s... | a diffuse core in saturn revealed by ring seismology |
many plants and animals will need to move large distances to track preferred climates, but fragmentation and barriers limit their movements. we asked to what degree and where species will be able to track suitable climates. we demonstrate that only 41% of us natural land area is currently connected enough to allow spec... | achieving climate connectivity in a fragmented landscape |
the carrington event is considered to be one of the most extreme space weather events in observational history within a series of magnetic storms caused by extreme interplanetary coronal mass ejections from a large and complex active region that emerged on the solar disk. in this article, we study the temporal and spat... | temporal and spatial evolutions of a large sunspot group and great auroral storms around the carrington event in 1859 |
context. wasp-121 b is a hot jupiter that was recently found to possess rich emission (day side) and transmission (limb) spectra, suggestive of the presence of a multitude of chemical species in the atmosphere.aims: we survey the transmission spectrum of wasp-121 b for line-absorption by metals and molecules at high sp... | hot exoplanet atmospheres resolved with transit spectroscopy (hearts). iv. a spectral inventory of atoms and molecules in the high-resolution transmission spectrum of wasp-121 b |
knowledge of intensities of rovibrational transitions of various molecules and theirs isotopic species in wide spectral and temperature ranges is essential for the modeling of optical properties of planetary atmospheres, brown dwarfs and for other astrophysical applications. theorets ("theoretical reims-tomsk spectral ... | theorets - an information system for theoretical spectra based on variational predictions from molecular potential energy and dipole moment surfaces |
over a large range of equilibrium temperatures, clouds shape the transmission spectrum of hot jupiter atmospheres, yet their composition remains unknown. recent observations show that the kepler light curves of some hot jupiters are asymmetric: for the hottest planets, the light curve peaks before secondary eclipse, wh... | transitions in the cloud composition of hot jupiters |
exoplanet detections have revolutionized astronomy, offering new insights into solar system architecture and planet demographics. while nearly 1,900 exoplanets have now been discovered and confirmed, none are still in the process of formation. transition disks, protoplanetary disks with inner clearings best explained b... | accreting protoplanets in the lkca 15 transition disk |
infrared radiation emitted from a planet contains information about the chemical composition and vertical temperature profile of its atmosphere. if upper layers are cooler than lower layers, molecular gases will produce absorption features in the planetary thermal spectrum. conversely, if there is a stratosphere—where ... | an ultrahot gas-giant exoplanet with a stratosphere |
aims: we determine the radii and masses of 293 nearby, bright m dwarfs of the carmenes survey. this is the first time that such a large and homogeneous high-resolution (r > 80 000) spectroscopic survey has been used to derive these fundamental stellar parameters.methods: we derived the radii using stefan-boltzmann's... | the carmenes search for exoplanets around m dwarfs. different roads to radii and masses of the target stars |
on water-dominated planets, warming from increased solar insolation is strongly amplified by the water vapor greenhouse feedback. as the sun brightens due to stellar evolution, earth will become uninhabitable due to rising temperatures. here we use a modified version of the community earth system model from the nationa... | the evolution of habitable climates under the brightening sun |
transition disks with large inner dust cavities are thought to host massive companions. however, the disk structure inside the companion orbit and how material flows toward an actively accreting star remain unclear. we present a high-resolution continuum study of inner disks in the cavities of 38 transition disks. meas... | dust-depleted inner disks in a large sample of transition disks through long-baseline alma observations |
hot jupiters, giant extrasolar planets with orbital periods shorter than ∼10 days, have long been thought to form at large radial distances, only to subsequently experience long-range inward migration. here, we offer the contrasting view that a substantial fraction of the hot jupiter population formed in situ via the c... | in situ formation and dynamical evolution of hot jupiter systems |
extensive rovibrational line lists were computed for nine isotopologues of the co molecule, namely, 12c16o, 12c17o, 12c18o, 13c16o, 13c17o, 13c18o, 14c16o, 14c17o, and 14c18o in the ground electronic state with v <= 41, δv <= 11, and j <= 150. the line intensity and position calculations were carried out using... | rovibrational line lists for nine isotopologues of the co molecule in the x 1σ+ ground electronic state |
the critical first step in the search for life on exoplanets over the next decade is to determine whether rocky planets transiting small m-dwarf stars possess atmospheres and, if so, what processes sculpt them over time. because of its broad wavelength coverage and improved resolution compared with previous instruments... | a jwst transmission spectrum of the nearby earth-sized exoplanet lhs 475 b |
icon (icosahedral nonhydrostatic) is a unified modeling system for global numerical weather prediction (nwp) and climate studies. validation of its dynamical core against a test suite for numerical weather forecasting has been recently published by zängl et al. (2014). in the present work, an extension of icon is prese... | large eddy simulation using the general circulation model icon |
on a planet with a population of more than 7 billion, how do we identify the millions of drought-afflicted people who face a real threat of livelihood disruption or death without humanitarian assistance? typically, these people are poor and heavily dependent on rainfed agriculture and livestock. most live in africa, ce... | recognizing the famine early warning systems network: over 30 years of drought early warning science advances and partnerships promoting global food security |
models of planet formation are built on underlying physical processes. in order to make sense of the origin of the planets we must first understand the origin of their building blocks. this review comes in two parts. the first part presents a detailed description of six key mechanisms of planet formation: the structure... | planet formation: key mechanisms and global models |
discs of gas and dust around million-year-old stars are a by-product of the star formation process and provide the raw material to form planets. hence, their evolution and dispersal directly impact what type of planets can form and affect the final architecture of planetary systems. here, we review empirical constraint... | the dispersal of planet-forming discs: theory confronts observations |
simulations suggest collisionless steady-state magnetic reconnection of harris-type current sheets proceeds with a rate of order 0.1, independent of dissipation mechanism. we argue this long-standing puzzle is a result of constraints at the magnetohydrodynamic (mhd) scale. we predict the reconnection rate as a function... | why does steady-state magnetic reconnection have a maximum local rate of order 0.1? |
the riddle posed by super-earths (1-4r⊕, 2-20m⊕) is that they are not jupiters: their core masses are large enough to trigger runaway gas accretion, yet somehow super-earths accreted atmospheres that weigh only a few percent of their total mass. we show that this puzzle is solved if super-earths formed late, as the las... | breeding super-earths and birthing super-puffs in transitional disks |
the detection of transiting exoplanets in time-series photometry requires the removal or modeling of instrumental and stellar noise. while instrumental systematics can be reduced using methods such as pixel level decorrelation, removing stellar trends while preserving transit signals proves challenging. as a result of ... | wōtan: comprehensive time-series detrending in python |
an increasingly well-resolved timetable of evolution provides new challenges and opportunities for evolutionary theory.the integration of fossils, phylogeny, and geochronology has resulted in an increasingly well-resolved timetable of evolution. life appears to have taken root before the earliest known minimally metamo... | the timetable of evolution |
this brief special communications article gives data for atomic abundances and mass fractions for the elemental and isotopic solar system composition, the atomic masses of the elements and their isotopes, the composition of the solar photosphere, and the compositions of the major chondritic meteorite groups. this addit... | relative atomic solar system abundances, mass fractions, and atomic masses of the elements and their isotopes, composition of the solar photosphere, and compositions of the major chondritic meteorite groups |
the detection of liquid water by the mars advanced radar for subsurface and ionosphere sounding (marsis) at the base of the south polar layered deposits in ultimi scopuli has reinvigorated the debate about the origin and stability of liquid water under present-day martian conditions. to establish the extent of subglaci... | multiple subglacial water bodies below the south pole of mars unveiled by new marsis data |
to date, the radial velocity (rv) method has been one of the most productive techniques for detecting and confirming extrasolar planetary candidates. unfortunately, stellar activity can induce rv variations which can drown out or even mimic planetary signals - and it is notoriously difficult to model and thus mitigate ... | a gaussian process framework for modelling stellar activity signals in radial velocity data |
radar sounding is a powerful geophysical approach for characterizing the subsurface conditions of terrestrial and planetary ice masses at local to global scales. as a result, a wide array of orbital, airborne, ground-based, and in situ instruments, platforms and data analysis approaches for radioglaciology have been de... | five decades of radioglaciology |
in this study, regional persistent haze events (rphes) in the beijing-tianjin-hebei (bth) region were identified based on the objective identification technique for regional extreme events for the period 1980-2013. the formation mechanisms of the severe rphes were investigated with focus on the atmospheric circulation ... | atmospheric circulation and dynamic mechanism for persistent haze events in the beijing-tianjin-hebei region |
the hadean eon, following the global-scale melting of the mantle1-3, is expected to be a dynamic period, during which earth experienced vastly different conditions. geologic records, however, suggest that the surface environment of earth was already similar to the present by the middle of the hadean4,5. under what cond... | a wet heterogeneous mantle creates a habitable world in the hadean |
this planetary boundaries framework update finds that six of the nine boundaries are transgressed, suggesting that earth is now well outside of the safe operating space for humanity. ocean acidification is close to being breached, while aerosol loading regionally exceeds the boundary. stratospheric ozone levels have sl... | earth beyond six of nine planetary boundaries |
we present our current understanding of the formation and early evolution of protostars, protoplanetary disks, and the driving of outflows as dictated by the interplay of magnetic fields and partially ionized gas in molecular cloud cores. in recent years, the field has witnessed enormous development through sub-millime... | the role of magnetic fields in the formation of protostars, disks, and outflows |
health condition identification of planetary gearboxes is crucial to reduce the downtime and maximize productivity. this paper aims to develop a novel fault diagnosis method based on modified multi-scale symbolic dynamic entropy (mmsde) and minimum redundancy maximum relevance (mrmr) to identify the different health co... | a fault diagnosis scheme for planetary gearboxes using modified multi-scale symbolic dynamic entropy and mrmr feature selection |
air quality is significantly influenced by the synoptic, regional and local meteorological conditions. this study aims at elucidating the relation between synoptic flow patterns and low visibility events of haze and fog over the north china plain (ncp), and the contribution of synoptic flow patterns and boundary layer ... | study on the synoptic flow patterns and boundary layer process of the severe haze events over the north china plain in january 2013 |
mapping and monitoring of land use land cover (lulc) changes in the himalayas is vital for sustainable development, planning and management. based on remote sensing (rs) and geographic information system (gis) techniques, the study is an attempt to monitor the changes in lulc patterns of rani khola watershed of sikkim ... | land use and land cover change detection using geospatial techniques in the sikkim himalaya, india |
atmospheric loss has controlled the history of martian habitability, removing most of the planet’s initial water through atomic hydrogen and oxygen escape from the upper atmosphere to space. in standard models, h and o escape in a stoichiometric 2:1 ratio because h reaches the upper atmosphere via long-lived molecular ... | elevated atmospheric escape of atomic hydrogen from mars induced by high-altitude water |
miri (the mid-infrared instrument for the james webb space telescope (jwst)) operates from 5 to 28.5 microns and combines over this range: 1.) unprecedented sensitivity levels; 2.) sub-arcsec angular resolution; 3.) freedom from atmospheric interference; 4.) the inherent stability of observing in space; and 5.) a suite... | the mid-infrared instrument for the james webb space telescope, i: introduction |
cloud entrainment, the mixing between cloudy and clear air at the boundary of clouds, constitutes one paradigm for the relevance of small scales in the earth system: by regulating cloud lifetimes, meter- and submeter-scale processes at cloud boundaries can influence planetary-scale properties. understanding cloud entra... | cloud-top entrainment in stratocumulus clouds |
we describe a 20 year survey carried out by the lick-carnegie exoplanet survey team (lces), using precision radial velocities from hires on the keck i telescope to find and characterize extrasolar planetary systems orbiting nearby f, g, k, and m dwarf stars. we provide here 60,949 precision radial velocities for 1624 s... | the lces hires/keck precision radial velocity exoplanet survey |
precise mass measurements of exoplanets discovered by the direct imaging or transit technique are required to determine planet bulk properties and potential habitability. furthermore, it is generally acknowledged that, for the foreseeable future, the extreme precision radial velocity (eprv) measurement technique is the... | extreme precision radial velocity working group final report |
why venus lacks plate tectonics remains an unanswered question in terrestrial planet evolution. there is observational evidence for subduction--a requirement for plate tectonics--on venus, but it is unclear why the features have characteristics of both mantle plumes and subduction zones. one explanation is that mantle ... | experimental and observational evidence for plume-induced subduction on venus |
the protoplanetary system hd 169142 is one of the few cases where a potential candidate protoplanet has recently been detected by direct imaging in the near-infrared. to study the interaction between the protoplanet and the disk itself, observations of the gas and dust surface density structure are needed. this paper r... | alma unveils rings and gaps in the protoplanetary system hd 169142: signatures of two giant protoplanets |
we present alma observations of 106 g-, k-, and m-type stars in the upper scorpius ob association hosting circumstellar disks. with these data, we measure the 0.88 mm continuum and 12co j = 3-2 line fluxes of disks around low-mass (0.14-1.66 m ⊙) stars at an age of 5-11 myr. of the 75 primordial disks in the sample, 53... | alma observations of circumstellar disks in the upper scorpius ob association |
context. the high accuracy radial velocity planet searcher (harps) spectrograph has been mounted since 2003 at the eso 3.6 m telescope in la silla and provides state-of-the-art stellar radial velocity (rv) measurements with a precision down to ∼1 m s-1. the spectra are extracted with a dedicated data-reduction software... | public harps radial velocity database corrected for systematic errors |
we introduce the ophiuchus disc survey employing alma (odisea), a project aiming to study the entire population of spitzer-selected protoplanetary discs in the ophiuchus molecular cloud (∼300 objects) from both millimetre continuum and co isotopologues data. here we present 1.3 mm/230 ghz continuum images of 147 target... | the ophiuchus disc survey employing alma (odisea) - i: project description and continuum images at 28 au resolution |
symplectic methods, in particular the wisdom-holman map, have revolutionized our ability to model the long-term, conservative dynamics of planetary systems. however, many astrophysically important effects are dissipative. the consequences of incorporating such forces into otherwise symplectic schemes are not always cle... | reboundx: a library for adding conservative and dissipative forces to otherwise symplectic n-body integrations |
transmission spectroscopy of exoplanets has the potential to provide precise measurements of atmospheric chemical abundances, in particular of hot jupiters whose large sizes and high temperatures make them conducive to such observations. to date, several transmission spectra of hot jupiters have revealed low amplitude ... | h2o abundances and cloud properties in ten hot giant exoplanets |
ground-based multi-axis differential optical absorption spectroscopy (max-doas) and lidar measurements were performed in shanghai, china, during may 2016 to investigate the vertical distribution of summertime atmospheric pollutants. in this study, vertical profiles of aerosol extinction coefficient, nitrogen dioxide (n... | observations of the vertical distributions of summertime atmospheric pollutants and the corresponding ozone production in shanghai, china |
this paper describes the scientific objectives and payloads of tianwen-1, china's first exploration mission to mars. an orbiter, carrying a lander and a rover, lifted-off in july 2020 for a journey to mars where it should arrive in february 2021. a suite of 13 scientific payloads, for in-situ and remote sensing, autono... | scientific objectives and payloads of tianwen-1, china's first mars exploration mission |
context. the study of dynamical processes in protoplanetary disks is essential to understand planet formation. in this context, transition disks are prime targets because they are at an advanced stage of disk clearing and may harbor direct signatures of disk evolution.aims: we aim to derive new constraints on the struc... | asymmetric features in the protoplanetary disk mwc 758 |
solar flares are often accompanied by filament/prominence eruptions (~104 k and ~1010−11 cm−3), sometimes leading to coronal mass ejections that directly affect the earth's environment1,2. `superflares' are found on some active solar-type (g-type main-sequence) stars3-5, but the filament eruption-coronal mass ejection ... | probable detection of an eruptive filament from a superflare on a solar-type star |
wind-driven sand transport generates atmospheric dust, forms dunes, and sculpts landscapes. however, it remains unclear how the sand flux scales with wind speed, largely because models do not agree on how particle speed changes with wind shear velocity. here, we present comprehensive measurements from three new field s... | wind-invariant saltation heights imply linear scaling of aeolian saltation flux with shear stress |
many geological and geochemical changes are recorded on earth between 3 and 2 ga. among the more important of these are the following: (1) increasing proportion of basalts with "arc-like" mantle sources; (2) an increasing abundance of basalts derived from enriched (em) and depleted (dm) mantle sources; (3) onset of a g... | a planet in transition: the onset of plate tectonics on earth between 3 and 2 ga? |
we present the seventh kepler planet candidate (pc) catalog, which is the first catalog to be based on the entire, uniformly processed 48-month kepler data set. this is the first fully automated catalog, employing robotic vetting procedures to uniformly evaluate every periodic signal detected by the q1-q17 data release... | planetary candidates observed by kepler. vii. the first fully uniform catalog based on the entire 48-month data set (q1-q17 dr24) |
we report on precise doppler measurements of l231-32 (toi-270), a nearby m dwarf (d = 22 pc, m⋆ = 0.39 m⊙, r⋆ = 0.38 r⊙), which hosts three transiting planets that were recently discovered using data from the transiting exoplanet survey satellite (tess). the three planets are 1.2, 2.4, and 2.1 times the size of earth a... | masses and compositions of three small planets orbiting the nearby m dwarf l231-32 (toi-270) and the m dwarf radius valley |
subduction is the major plate driving force, and the strength of the subducting plate controls many aspects of the thermochemical evolution of earth. each subducting plate experiences intense normal faulting1-9 during bending that accommodates the transition from horizontal to downwards motion at the outer rise at tren... | dynamic slab segmentation due to brittle-ductile damage in the outer rise |
over the history of planetary exploration, atmospheric entry vehicles have been used to deliver probes and landers to venus, mars, jupiter, and titan. while the entry vehicles are tools for furthering scientific exploration, by delivering probes and landers which perform in-situ exploration, the entry vehicle and traje... | a survey of the design trade space for atmospheric entry, descent, and landing missions |
the (u-th)/he dating technique is an essential tool in earth science research with diverse thermochronologic, geochronologic, and detrital applications. it is now used in a wide range of tectonic, structural, petrological, sedimentary, geomorphic, volcanological, and planetary studies. while in some circumstances the i... | (u-th)/he chronology: part 2. considerations for evaluating, integrating, and interpreting conventional individual aliquot data |
the molecules with alma at planet-forming scales (maps) large program provides a detailed, high-resolution (~10-20 au) view of molecular line emission in five protoplanetary disks at spatial scales relevant for planet formation. here we present a systematic analysis of chemical substructures in 18 molecular lines towar... | molecules with alma at planet-forming scales (maps). iii. characteristics of radial chemical substructures |
the nature of the early martian climate is one of the major unanswered questions of planetary science. key challenges remain, but a new wave of orbital and in situ observations and improvements in climate modeling have led to significant advances over the past decade. multiple lines of geologic evidence now point to an... | the climate of early mars |
in 2017, the california-kepler survey (cks) published its first data release (dr1) of high-resolution optical spectra of 1305 planet hosts. refined cks planet radii revealed that small planets are bifurcated into two distinct populations, super-earths (smaller than 1.5 r ⊕) and sub-neptunes (between 2.0 and 4.0 r ⊕), w... | the california-kepler survey. x. the radius gap as a function of stellar mass, metallicity, and age |
we present calculations of the occurrence rate of small close-in planets around low-mass dwarf stars using the known planet populations from the kepler and k2 missions. applying completeness corrections clearly reveals the radius valley in the maximum a posteriori occurrence rates as a function of orbital separation an... | evolution of the radius valley around low-mass stars from kepler and k2 |
titan is the only moon with a substantial atmosphere, the only other thick n2 atmosphere besides earth's, the site of extraordinarily complex atmospheric chemistry that far surpasses any other solar system atmosphere, and the only other solar system body with stable liquid currently on its surface. the connection betwe... | titan's atmosphere and climate |
the gas-phase co abundance (relative to hydrogen) in protoplanetary disks decreases by up to two orders of magnitude from its interstellar medium value of ∼10-4, even after accounting for freeze-out and photodissociation. previous studies have shown that while local chemical processing of co and the sequestration of co... | co depletion in protoplanetary disks: a unified picture combining physical sequestration and chemical processing |
satellite derived vegetation indices (vis) are broadly used in ecological research, ecosystem modeling, and land surface monitoring. the normalized difference vegetation index (ndvi), perhaps the most utilized vi, has countless applications across ecology, forestry, agriculture, wildlife, biodiversity, and other discip... | a dynamic landsat derived normalized difference vegetation index (ndvi) product for the conterminous united states |
carbon is an essential element for life but how much can be delivered to young planets is still an open question. the chemical characterization of planet-forming disks is a crucial step in our understanding of the diversity and habitability of exoplanets. very low-mass stars (less than 0.2 m⊙) are interesting targets b... | a rich hydrocarbon chemistry and high c to o ratio in the inner disk around a very low-mass star |
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