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the dwarf planet ceres is known to host phyllosilicate minerals at its surface, but their distribution and origin have not previously been determined. we used the spectrometer onboard the dawn spacecraft to map their spatial distribution on the basis of diagnostic absorption features in the visible and near-infrared sp... | distribution of phyllosilicates on the surface of ceres |
we present an asymptotically and unconditionally stable numerical method to account for the momentum transfer between multiple species. momentum is conserved to machine precision. this implies that the asymptotic equilibrium corresponds to the velocity of the center of mass. aimed at studying dust dynamics, we implemen... | asymptotically stable numerical method for multispecies momentum transfer: gas and multifluid dust test suite and implementation in fargo3d |
the upper scorpius ob association is the nearest region of recent massive star formation and thus an important benchmark for investigations concerning stellar evolution and planet formation timescales. we present nine eclipsing binaries (ebs) in upper scorpius, three of which are newly reported here and all of which we... | age determination in upper scorpius with eclipsing binaries |
the rosina mass spectrometer dfms on board esa's rosetta spacecraft detected the major isotopes of the noble gases argon, krypton, and xenon in the coma of comet 67p/churyumov-gerasimenko. earlier, it has been shown that xenon exhibits an isotopic composition distinct from anywhere else in the solar system. however, ar... | krypton isotopes and noble gas abundances in the coma of comet 67p/churyumov-gerasimenko |
the polarization state of electromagnetic radiation scattered by atmospheric particles such as aerosols, cloud droplets, or ice crystals contains much more information about the optical and microphysical properties than the total intensity alone. for this reason an increasing number of polarimetric observations are per... | iprt polarized radiative transfer model intercomparison project - phase a |
absorption of high-energy radiation in planetary thermospheres is generally believed to lead to the formation of planetary winds. the resulting mass-loss rates can affect the evolution, particularly of small gas planets. we present 1d, spherically symmetric hydrodynamic simulations of the escaping atmospheres of 18 hot... | simulating the escaping atmospheres of hot gas planets in the solar neighborhood |
observations of the warm neptune gj 436 b were performed with hst/stis at three different epochs (2012, 2013, 2014) in the stellar lyman-α line. they showed deep, repeated transits that were attributed to a giant exosphere of neutral hydrogen. the low radiation pressure from the m-dwarf host star was shown to play a ma... | an evaporating planet in the wind: stellar wind interactions with the radiatively braked exosphere of gj 436 b |
compared to the earth, the exoplanet kepler-78b has a similar size (1.2 r⊕) and an orbital period a thousand times shorter (8.5 h). it is currently the smallest planet for which the mass, radius, and dayside brightness have all been measured. kepler-78b is an exemplar of the ultra-short-period (usp) planets, a category... | kepler-78 and the ultra-short-period planets |
we performed a comprehensive demographic study of the co extent relative to dust of the disk population in the lupus clouds in order to find indications of dust evolution and possible correlations with other disk properties. we increased the number of disks of the region with measured rco and rdust from observations wi... | measuring the ratio of the gas and dust emission radii of protoplanetary disks in the lupus star-forming region |
the detection of a wide range of substructures such as rings, cavities, and spirals has become a common outcome of high spatial resolution imaging of protoplanetary disks, both in the near-infrared scattered light and in the thermal millimetre continuum emission. the most frequent interpretation of their origin is the ... | perturbers: sphere detection limits to planetary-mass companions in protoplanetary disks |
as host to two accreting planets, pds 70 provides a unique opportunity to probe the chemical complexity of atmosphere-forming material. we present alma band 6 observations of the pds 70 disk and report the first chemical inventory of the system. with a spatial resolution of 0"4-0"5 (~50 au), 12 species are detected, in... | the chemical inventory of the planet-hosting disk pds 70 |
we report the detection of the first circumbinary planet (cbp) found by transiting exoplanet survey satellite (tess). the target, a known eclipsing binary, was observed in sectors 1 through 12 at 30 minute cadence and in sectors 4 through 12 at 2 minute cadence. it consists of two stars with masses of 1.1 m⊙ and 0.3 m⊙... | toi-1338: tess' first transiting circumbinary planet |
massive stars, at least ∼10 times more massive than the sun, have two key properties that make them the main drivers of evolution of star clusters, galaxies, and the universe as a whole. on the one hand, the outer layers of massive stars are so hot that they produce most of the ionizing ultraviolet radiation of galaxie... | towards a unified view of inhomogeneous stellar winds in isolated supergiant stars and supergiant high mass x-ray binaries |
air pollution simulations critically depend on the quality of the underlying meteorology. in phase 2 of the air quality model evaluation international initiative (aqmeii-2), thirteen modeling groups from europe and four groups from north america operating eight different regional coupled chemistry and meteorology model... | comparative analysis of meteorological performance of coupled chemistry-meteorology models in the context of aqmeii phase 2 |
a key stage in planet formation is the evolution of a gaseous and magnetized solar nebula. however, the lifetime of the nebular magnetic field and nebula are poorly constrained. we present paleomagnetic analyses of volcanic angrites demonstrating that they formed in a near-zero magnetic field (<0.6 microtesla) at 45... | lifetime of the solar nebula constrained by meteorite paleomagnetism |
delhi, india, is the second most populated city in the world and routinely experiences some of the highest particulate matter concentrations of any megacity on the planet, posing acute challenges to public health (world health organization, 2018). however, the current understanding of the sources and dynamics of pm pol... | sources and atmospheric dynamics of organic aerosol in new delhi, india: insights from receptor modeling |
the nature and evolution of earth's crust during the hadean and eoarchean is largely unknown owing to a paucity of material preserved from this period. however, clues may be found in the chemical composition of refractory minerals that initially grew in primordial material but were subsequently incorporated into younge... | widespread reworking of hadean-to-eoarchean continents during earth's thermal peak |
astrophysical ices are exposed to different radiation fields including photons, electrons and ions. the latter stem from interstellar cosmic rays (cr), the solar and stellar winds, shock waves or are trapped in the magnetospheres of giant planets. we briefly discuss the physics of energy deposition by ion ir radiation ... | modification of ices by cosmic rays and solar wind |
we review the results of an extensive campaign to determine the physical, geological, and dynamical properties of asteroid (101955) bennu. this investigation provides information on the orbit, shape, mass, rotation state, radar response, photometric, spectroscopic, thermal, regolith, and environmental properties of ben... | the osiris-rex target asteroid (101955) bennu: constraints on its physical, geological, and dynamical nature from astronomical observations |
in the search for a record of eustatic sea level change on glacial-interglacial timescales, the seychelles ranks as one of the best places on the planet to study. owing to its location with respect to the former margins of northern hemisphere ice sheets that wax and wane on orbital cycles, the local-or relative-sea lev... | tropical tales of polar ice: evidence of last interglacial polar ice sheet retreat recorded by fossil reefs of the granitic seychelles islands |
water scarcity is rapidly spreading across the planet, threatening the population across the five continents and calling for global sustainable solutions. water reclamation is the most ecological approach for supplying clean drinking water. however, current water purification technologies are seldom sustainable, due to... | protein nanofibrils for next generation sustainable water purification |
we are well and truly in the anthropocene. humans can no longer be considered as mere external drivers or boundary conditions in the hydrologic systems we study. the interactions and feedbacks between human actions and water cycle dynamics on the planet, combined with the evolution of human norms/values in relation to ... | debates—perspectives on socio-hydrology: changing water systems and the "tyranny of small problems"—socio-hydrology |
magnetized winds may be important in dispersing protoplanetary disks and influencing planet formation. we carry out global magnetohydrodynamic simulations in axisymmetry, coupled with ray-tracing radiative transfer, consistent thermochemistry, and non-ideal mhd diffusivities. magnetized models lacking euv photons (hν &... | global simulations of protoplanetary disk outflows with coupled non-ideal magnetohydrodynamics and consistent thermochemistry |
a giant planet embedded in a protoplanetary disk forms a gap. an analytic relationship among the gap depth, planet mass mp, disk aspect ratio hp, and viscosity α has been found recently, and the gap depth can be written in terms of a single parameter k={{({{m}p}/{{m}*})}2}hp-5{{α }-1}. we discuss how observed gap featu... | mass estimates of a giant planet in a protoplanetary disk from the gap structures |
surveys of young star-forming regions have discovered a growing population of planetary-mass (<13 mjup) companions around young stars1. there is an ongoing debate as to whether these companions formed like planets (that is, from the circumstellar disk)2, or if they represent the low-mass tail of the star-formation p... | constraints on the spin evolution of young planetary-mass companions |
the moon-forming impact and the subsequent evolution of the proto-earth is strongly dependent on the properties of materials at the extreme conditions generated by this violent collision. we examine the high pressure behavior of mgo, one of the dominant constituents in earth's mantle, using high-precision, plate impact... | shock response and phase transitions of mgo at planetary impact conditions |
understanding the formation and evolution of giant planets (≥1 mjup) at wide orbital separation (≥5 au) is one of the goals of direct imaging. over the past 15 yr, many surveys have placed strong constraints on the occurrence rate of wide-orbit giants, mostly based on non-detections, but very few have tried to make a d... | the vlt/naco large program to probe the occurrence of exoplanets and brown dwarfs at wide orbits. iv. gravitational instability rarely forms wide, giant planets |
isotope abundance ratios have an important role in astronomy and planetary sciences, providing insights into the origin and evolution of the solar system, interstellar chemistry and stellar nucleosynthesis1,2. in contrast to deuterium/hydrogen ratios, carbon isotope ratios are found to be roughly constant (around 89) i... | the 13co-rich atmosphere of a young accreting super-jupiter |
the composition of gas and solids in protoplanetary discs sets the composition of planets that form out of them. recent chemical models have shown that the composition of gas and dust in discs evolves on myr time-scales, with volatile species disappearing from the gas phase. however, discs evolve due to gas accretion a... | planet-forming material in a protoplanetary disc: the interplay between chemical evolution and pebble drift |
interstellar comets offer direct samples of volatiles from distant protoplanetary disks. 2i/borisov is the first notably active interstellar comet discovered in our solar system1. comets are condensed samples of the gas, ice and dust that were in a star's protoplanetary disk during the formation of its planets, and inf... | the carbon monoxide-rich interstellar comet 2i/borisov |
we collect observational evidence that supports the scheme of mass transfer on the nucleus of comet 67p/churyumov-gerasimenko. the obliquity of the rotation axis of 67p causes strong seasonal variations. during perihelion the southern hemisphere is four times more active than the north. northern territories are widely ... | seasonal mass transfer on the nucleus of comet 67p/chuyumov-gerasimenko |
the axion, motivated as a solution to the strong c p problem, is also a viable dark matter candidate. the axion field takes random values in causally disconnected regions if the symmetry breaking that establishes the particle occurs after inflation, leading to white-noise density fluctuations at low wave numbers and fo... | simulations of axion minihalos |
exoplanets orbiting m-dwarfs present a valuable opportunity for their detection and atmospheric characterization. this is evident from recent inferences of h2o in such atmospheres, including that of the habitable-zone exoplanet k2-18b. with a bulk density between earth and neptune, k2-18b may be expected to possess a h... | the interior and atmosphere of the habitable-zone exoplanet k2-18b |
large-scale vertical magnetic fields are believed to play a key role in the evolution of protoplanetary discs. associated with non-ideal effects, such as ambipolar diffusion, they are known to launch a wind that could drive accretion in the outer part of the disc (r > 1 au). they also potentially lead to self-organi... | ring formation and dust dynamics in wind-driven protoplanetary discs: global simulations |
in this review/tutorial we explore planetary nebulae as a stage in the evolution of low-to-intermediate-mass stars, as major contributors to the mass and chemical enrichment of the interstellar medium, and as astrophysical laboratories. we discuss many observed properties of planetary nebulae, placing particular emphas... | planetary nebulae: sources of enlightenment |
an increasing number of observations have shown that gaseous debris discs are not an exception. however, until now, we only knew of cases around a stars. here we present the first detection of 12co (2-1) disc emission around an f star, hd 181327, obtained with the atacama large millimeter/submillimeter array (alma) obs... | exocometary gas in the hd 181327 debris ring |
the filamentary nature of accretion streams found around embedded sources suggests that protostellar disks experience heterogenous infall from the star-forming environment, consistent with the accretion behavior onto star-forming cores in top-down star-cluster formation simulations. this may produce disk substructures ... | anisotropic infall and substructure formation in embedded disks |
clouds play an important role in the atmospheres of planetary bodies. it is expected that, like all the planetary bodies in our solar system, exoplanet atmospheres will also have substantial cloud coverage, and evidence is mounting for clouds in a number of hot jupiters. to better characterise planetary atmospheres, we... | transmission spectral properties of clouds for hot jupiter exoplanets |
proxima b is a terrestrial-mass planet in the habitable zone of proxima centauri. proxima centauri’s high stellar activity, however, casts doubt on the habitability of proxima b: sufficiently bright and frequent flares and any associated proton events may destroy the planet’s ozone layer, allowing lethal levels of uv f... | the first naked-eye superflare detected from proxima centauri |
silicon and mg in differentiated rocky bodies exhibit heavy isotope enrichments that have been attributed to evaporation of partially or entirely molten planetesimals. we evaluate the mechanisms of planetesimal evaporation in the early solar system and the conditions that controlled attendant isotope fractionations. en... | near-equilibrium isotope fractionation during planetesimal evaporation |
earth and the moon are shown here to have indistinguishable oxygen isotope ratios, with a difference in δ‧17o of -1 ± 5 parts per million (2 standard error). on the basis of these data and our new planet formation simulations that include a realistic model for primordial oxygen isotopic reservoirs, our results favor vi... | oxygen isotopic evidence for vigorous mixing during the moon-forming giant impact |
the discovery of more than 4500 extrasolar planets has created a need for modeling their interior structure and dynamics. given the prominence of iron in planetary interiors, we require accurate and precise physical properties at extreme pressure and temperature. a first-order property of iron is its melting point, whi... | measuring the melting curve of iron at super-earth core conditions |
space-based high-contrast imaging mission concepts for studying rocky exoplanets in reflected light are currently under community study. we develop an inverse modeling framework to estimate the science return of such missions given different instrument design considerations. by combining an exoplanet albedo model, inst... | characterizing earth analogs in reflected light: atmospheric retrieval studies for future space telescopes |
forecasting the geomagnetic effects of solar storms, known as coronal mass ejections (cmes), is currently severely limited by our inability to predict the magnetic field configuration in the cme magnetic core and by observational effects of a single spacecraft trajectory through its 3-d structure. cme magnetic flux rop... | forward modeling of coronal mass ejection flux ropes in the inner heliosphere with 3dcore |
the so-called ultra-diffuse galaxy ngc 1052-df2 was announced to be a galaxy lacking dark matter based on a spectroscopic study of its constituent globular clusters. here we present the first spectroscopic analysis of the stellar body of this galaxy using the muse integral-field spectrograph at the (eso) very large tel... | the ultra-diffuse galaxy ngc 1052-df2 with muse. i. kinematics of the stellar body |
volcanic edifices are abundant on rocky bodies of the inner solar system. in the cold outer solar system, volcanism can occur on solid bodies with a water-ice shell, but derived cryovolcanic constructs have proved elusive. we report the discovery, using dawn framing camera images, of a landform on dwarf planet ceres th... | cryovolcanism on ceres |
we present a collection of 450 598 eclipsing and ellipsoidal binary systems detected in the ogle fields toward the galactic bulge. the collection consists of binary systems of all types: detached, semi-detached, and contact eclipsing binaries, rs cvn stars, cataclysmic variables, hw vir binaries, double periodic variab... | the ogle collection of variable stars. over 450 000 eclipsing and ellipsoidal binary systems toward the galactic bulge |
we analyse the transmission spectra of kelt-20b/mascara-2b to search for possible thermal inversion agents. the data consist of three transits obtained using harpsn and one using carmenes. we removed stellar and telluric lines before cross-correlating the residuals with spectroscopic templates produced using a 1d plane... | searching for thermal inversion agents in the transmission spectrum of kelt-20b/mascara-2b: detection of neutral iron and ionised calcium h&k lines |
we present a visible-light full orbital phase curve of the transiting planet wasp-18b measured by the tess mission. the phase curve includes the transit, secondary eclipse, and sinusoidal modulations across the orbital phase shaped by the planet’s atmospheric characteristics and the star-planet gravitational interactio... | tess full orbital phase curve of the wasp-18b system |
planets are born from disks of gas and dust, and observations of protoplanetary disks are used to constrain the initial conditions of planet formation. however, dust mass measurements of class ii disks with alma have called into question whether they contain enough solids to build the exoplanets that have been detected... | the mass budgets and spatial scales of exoplanet systems and protoplanetary disks |
the streaming instability (si) is a mechanism to aerodynamically concentrate solids in protoplanetary disks and facilitate the formation of planetesimals. recent numerical modeling efforts have demonstrated the increasing complexity of the initial mass distribution of planetesimals. to better constrain this distributio... | demographics of planetesimals formed by the streaming instability |
we analyze two high-resolution spectral transit time series of the hot jupiter hat-p-32 b obtained with the carmenes spectrograph. our new xmm-newton x-ray observations of the system show that the fast-rotating f-type host star exhibits a high x-ray luminosity of 2.3 × 1029 erg s−1 (5-100 å), corresponding to a flux of... | hα and he i absorption in hat-p-32 b observed with carmenes. detection of roche lobe overflow and mass loss |
transit surveys indicate that there is a deficit of neptune-sized planets on close-in orbits. if this "neptune desert" is entirely cleared out by atmospheric mass loss, then planets at its upper edge should only be marginally stable against photoevaporation, exhibiting strong outflow signatures in tracers like the meta... | the upper edge of the neptune desert is stable against photoevaporation |
the first discovered extrasolar worlds-giant, "hot jupiter" planets on short-period orbits-came as a surprise to solar system-centric models of planet formation, prompting the development of new theories for planetary system evolution. the near absence of observed nearby planetary companions to hot jupiters has been wi... | evidence for hidden nearby companions to hot jupiters |
since early 2019, the insight mission has proven that mars is seismically active, with more than 900 seismic events recorded. among them, several events have characteristics close to terrestrial tectonic earthquakes. most of these events are located on the major graben system of cerberus fossae and, a little further no... | seismic sources of insight marsquakes and seismotectonic context of elysium planitia, mars |
the earth is a unique planet, which has been highly evolved, diversified and complicated through geologic time, and underwent many key events, including giant impact, magma ocean, core formation, large-scale mantle differentiation and late heavy bombardment, especially in its dawn. but, our knowledge of early earth is ... | geology of the eoarchean, > 3.95 ga, nulliak supracrustal rocks in the saglek block, northern labrador, canada: the oldest geological evidence for plate tectonics |
markku kulmala calls for continuous, comprehensive monitoring of interactions between the planet's surface and atmosphere. | build a global earth observatory |
terrestrial planets are thought to experience episode(s) of large-scale melting early in their history. fractionation during magma-ocean freezing leads to unstable stratification within the related cumulate layers due to progressive iron enrichment upward, but the effects of incremental cumulate overturns during mo cry... | reconciling magma-ocean crystallization models with the present-day structure of the earth's mantle |
we study the red-optical photometry of the ultrahot jupiter wasp-121 b as observed by the transiting exoplanet survey satellite (tess) and model its atmosphere through a radiative transfer simulation. given its short orbital period of ∼1.275 days, inflated state, and bright host star, wasp-121 b is exceptionally favora... | tess observations of the wasp-121 b phase curve |
we present results from a high-contrast adaptive optics imaging search for giant planets and brown dwarfs (gsim1 m jup) around 122 newly identified nearby (lsim40 pc) young m dwarfs. half of our targets are younger than 135 myr and 90% are younger than the hyades (620 myr). after removing 44 close stellar binaries (imp... | planets around low-mass stars (palms). iv. the outer architecture of m dwarf planetary systems |
context. while planet formation is thought to occur early in the history of a protoplanetary disk, the presence of planets embedded in disks, or of other processes driving disk evolution, might be traced from their imprints on the disk structure.aims: we study the morphology of the disk around the t tauri star hd 14300... | shadows and asymmetries in the t tauri disk hd 143006: evidence for a misaligned inner disk |
the lucy mission is a nasa discovery-class mission to send a highly capable and robust spacecraft to investigate seven primitive bodies near both the l4 and l5 lagrange points with jupiter: the jupiter trojan asteroids. these planetesimals from the outer planetary system have been preserved since early in solar system ... | lucy mission to the trojan asteroids: science goals |
planetary debris disks around other stars are analogous to the asteroid and kuiper belts in the solar system. their structure reveals the configuration of small bodies and provides hints for the presence of planets. the nearby star fomalhaut hosts one of the most prominent debris disks, resolved by the hubble space tel... | spatially resolved imaging of the inner fomalhaut disk using jwst/miri |
while cooler giant planets are often observed with nonzero eccentricities, the short-period circular orbits of hot jupiters suggest that they lose orbital energy and angular momentum due to tidal interactions with their host stars. however, orbital decay has never been unambiguously observed. we use data from gaia data... | hot jupiters are destroyed by tides while their host stars are on the main sequence |
the earth has warmed in the last century and a large component of that warming has been attributed to increased anthropogenic greenhouse gases. there are also numerous processes that introduce strong, regionalized variations to the overall warming trend. however, the ability of a forcing to change the surface air tempe... | differences in the efficacy of climate forcings explained by variations in atmospheric boundary layer depth |
while it is widely accepted that planets are formed in protoplanetary disks, there is still much debate on when this process happens. in a few cases protoplanets have been directly imaged, but for the vast majority of systems, disk gaps and cavities—seen especially in dust continuum observations—have been the strongest... | a case of simultaneous star and planet formation |
context. the detection of a super-earth and three mini-neptunes transiting the bright (v = 9.2 mag) star hd 108236 (also known as toi-1233) was recently reported on the basis of tess and ground-based light curves.aims: we perform a first characterisation of the hd 108236 planetary system through high-precision cheops p... | cheops observations of the hd 108236 planetary system: a fifth planet, improved ephemerides, and planetary radii |
this study provides the first comprehensive assessment of regional climate model version 4.6.1 (regcm4) for the tibetan plateau (tp) region. a wide range of model configurations were analyzed with different parameterizations employed to represent cumulus convection (kuo, grell, emanuel, kain, and tiedtke), land surface... | sensitivity studies and comprehensive evaluation of regcm4.6.1 high-resolution climate simulations over the tibetan plateau |
the urban heat island intensity (uhii) is the temperature difference between urban areas and their rural surroundings. it is commonly attributed to changes in the underlying surface structure caused by urbanization. air pollution caused by aerosol particles can affect the uhii through changing (1) the surface energy ba... | the mechanisms and seasonal differences of the impact of aerosols on daytime surface urban heat island effect |
the silk road pattern (srp), which is the leading mode of upper-tropospheric meridional wind anomalies over midlatitude eurasia, has been widely used to explain the impacts of the summer north atlantic oscillation (snao) on east asian climate. however, the relationship between the snao and srp has not been fully elabor... | the relationship between the north atlantic oscillation and the silk road pattern in summer |
transmission spectroscopy provides a powerful probe of the atmospheric properties of transiting exoplanets. to date, studies of exoplanets in transit have focused on inferring their atmospheric properties such as chemical compositions, cloud/haze properties, and temperature structures. however, surface inhomogeneities ... | retrieval of planetary and stellar properties in transmission spectroscopy with aura |
researchers apply an economic model to trade-offs facing the un's ambitious sustainable development goals agenda.the 17 sustainable development goals (sdgs) call for a comprehensive new approach to development rooted in planetary boundaries, equity, and inclusivity. the wide scope of the sdgs will necessitate unprecede... | assessing the land resource–food price nexus of the sustainable development goals |
jiram is an imager/spectrometer on board the juno spacecraft bound for a polar orbit around jupiter. jiram is composed of ir imager and spectrometer channels. its scientific goals are to explore the jovian aurorae and the planet's atmospheric structure, dynamics and composition. this paper explains the characteristics ... | jiram, the jovian infrared auroral mapper |
amidst declarations of planetary emergency and reports that the window for limiting climate change to 1.5 °c is rapidly closing, global average temperatures and fossil fuel emissions continue to rise. global fossil co2 emissions have grown three years consecutively: +1.5% in 2017, +2.1% in 2018, and our slower central ... | persistent fossil fuel growth threatens the paris agreement and planetary health |
observations of multiple rotational transitions from a single molecule allow for unparalleled constraints on the physical conditions of the emitting region. we present an analysis of cs in tw hya using the j = 7-6, 5-4 and 3-2 transitions imaged at ∼0.″5 spatial resolution, resulting in a temperature and column density... | temperature, mass, and turbulence: a spatially resolved multiband non-lte analysis of cs in tw hya |
context. the consortium of the spectro-polarimetric high-contrast exoplanet research installed at the very large telescope (sphere/vlt) has been operating its guaranteed observation time (260 nights over five years) since february 2015. the main part of this time (200 nights) is dedicated to the detection and character... | astrometric and photometric accuracies in high contrast imaging: the sphere speckle calibration tool (specal) |
the organic content of protoplanetary disks sets the initial compositions of planets and comets, thereby influencing subsequent chemistry that is possible in nascent planetary systems. we present observations of the complex nitrile-bearing species ch3cn and hc3n toward the disks around the t tauri stars as 209, im lup,... | a survey of ch3cn and hc3n in protoplanetary disks |
context. when a planet becomes massive enough, it gradually carves a partial gap around its orbit in the protoplanetary disk. a pressure maximum can be formed outside the gap where solids that are loosely coupled to the gas, typically in the pebble size range, can be trapped. the minimum planet mass for building such a... | how much does turbulence change the pebble isolation mass for planet formation? |
sphere (beuzit et al,. 2019) has now been in operation at the vlt for more than 5 years, demonstrating a high level of performance. sphere has produced outstanding results using a variety of operating modes, primarily in the field of direct imaging of exoplanetary systems, focusing on exoplanets as point sources and ci... | sphere+: imaging young jupiters down to the snowline |
context. lhs 1140 is an m dwarf known to host two transiting planets at orbital periods of 3.77 and 24.7 days. they were detected with harps and spitzer. the external planet (lhs 1140 b) is a rocky super-earth that is located in the middle of the habitable zone of this low-mass star. all these properties place this sys... | planetary system lhs 1140 revisited with espresso and tess |
context. complex organic molecules (coms) are thought to form on icy dust grains in the earliest phase of star formation. the evolution of these coms from the youngest class 0/i protostellar phases toward the more evolved class ii phase is still not fully understood. since planet formation seems to start early, and mat... | complex organic molecules in low-mass protostars on solar system scales. i. oxygen-bearing species |
we have conducted a survey of young single and multiple systems in the taurus-auriga star-forming region with the atacama large millimeter array (alma), substantially improving both the spatial resolution and sensitivity with which individual protoplanetary disks in these systems have been observed. these alma observat... | resolved young binary systems and their disks |
strong absorption signatures in the helium line at 1083 nm have recently been detected in transmission spectra of several close-in exoplanets. this absorption line originates from neutral helium atoms in an excited, metastable 23s state. the population of helium atoms in this excited state is governed by the spectral s... | helium absorption at 1083 nm from extended exoplanet atmospheres: dependence on stellar radiation |
the process by which the sun affects the terrestrial environment on short timescales is predominately driven by the amount of magnetic reconnection between the solar wind and earth's magnetosphere. reconnection occurs most efficiently when the solar wind magnetic field has a southward component. the most severe impacts... | predicting the magnetic vectors within coronal mass ejections arriving at earth: 1. initial architecture |
hybrid symplectic integrators such as mercury are widely used to simulate complex dynamical phenomena in planetary dynamics that could otherwise not be investigated. a hybrid integrator achieves high accuracy during close encounters by using a high-order integration scheme for the duration of the encounter while otherw... | hybrid symplectic integrators for planetary dynamics |
atmospheric characterization of temperate, rocky planets is the holy grail of exoplanet studies. these worlds are at the limits of our capabilities with current instrumentation in transmission spectroscopy and challenge our state-of-the-art statistical techniques. here we present the transmission spectrum of the temper... | hubble wfc3 spectroscopy of the habitable-zone super-earth lhs 1140 b |
small, cool planets represent the typical end-products of planetary formation. studying the architectures of these systems, measuring planet masses and radii, and observing these planets’ atmospheres during transit directly informs theories of planet assembly, migration, and evolution. here we report the discovery of t... | a nearby m star with three transiting super-earths discovered by k2 |
we have mapped the major-element composition of mercury's surface from orbital messenger x-ray spectrometer measurements. these maps constitute the first global-scale survey of the surface composition of a solar system body conducted with the technique of planetary x-ray fluorescence. full maps of mg and al, together w... | evidence for geochemical terranes on mercury: global mapping of major elements with messenger's x-ray spectrometer |
building the terrestrial planets has been a challenge for planet formation models. in particular, classical theories have been unable to reproduce the small mass of mars and instead predict that a planet near 1.5 astronomical units (au) should roughly be the same mass as earth. recently, a new model called viscously st... | growing the terrestrial planets from the gradual accumulation of sub-meter sized objects |
the mass of a protoplanetary disk limits the formation and future growth of any planet. masses of protoplanetary disks are usually calculated from measurements of the dust continuum emission by assuming an interstellar gas-to-dust ratio. to investigate the utility of co as an alternate probe of disk mass, we use alma t... | an alma survey of co isotopologue emission from protoplanetary disks in chamaeleon i |
as protostars evolve from optically faint/infrared-bright (class i) sources to optically bright/infrared-faint (class ii) the solid material in their surrounding disks accumulates into planetesimals and protoplanets. the nearby, young ophiuchus star-forming region contains hundreds of protostars in a range of evolution... | the ophiuchus disk survey employing alma (odisea): disk dust mass distributions across protostellar evolutionary classes |
two studies utilizing sparse aperture-masking (sam) interferometry and h αdifferential imaging have reported multiple jovian companions around the young solar-mass star, lkca 15 (lkca 15 bcd): the first claimed direct detection of infant, newly formed planets (“protoplanets”). we present new near-infrared direct imagin... | no clear, direct evidence for multiple protoplanets orbiting lkca 15: lkca 15 bcd are likely inner disk signals |
context. the detection of radio emissions from exoplanets will open up a vibrant new research field. observing planetary auroral radio emission is the most promising method to detect exoplanetary magnetic fields, the knowledge of which will provide valuable insights into the planet's interior structure, atmospheric esc... | the search for radio emission from the exoplanetary systems 55 cancri, υ andromedae, and τ boötis using lofar beam-formed observations |
we aim at estimating the dust scale height of protoplanetary disks from millimeter continuum observations. first, we present a general expression of intensity of a ring in a protoplanetary disk and show that we can constrain the dust scale height by the azimuthal intensity variation. then, we apply the presented method... | estimate on dust scale height from the alma dust continuum image of the hd 163296 protoplanetary disk |
wasp-52b is a low-density hot jupiter orbiting a moderately active k2v star. previous low-resolution studies have revealed a cloudy atmosphere and found atomic na above the cloud deck. here we report on the detection of excess absorption at the na doublet, the hα line, and the k d1 line. we derived a high-resolution tr... | detection of na, k, and hα absorption in the atmosphere of wasp-52b using espresso |
ultra-hot jupiters are gas giants planets whose dayside temperature is greater than 2200 k as a consequence of the strong irradiation received from the host star. these kinds of objects are perfect laboratories to study the chemistry of exoplanetary upper atmospheres via transmission spectroscopy. exo-atmospheric absor... | detection of fe i and fe ii in the atmosphere of mascara-2b using a cross-correlation method |
aerospace technologies are crucial for modern civilization; space-based infrastructure underpins weather forecasting, communications, terrestrial navigation and logistics, planetary observations, solar monitoring, and other indispensable capabilities. extraplanetary exploration -- including orbital surveys and (more re... | precision magnetometers for aerospace applications: a review |
the system of two transiting neptune-sized planets around the bright, young m-dwarf au mic provides a unique opportunity to test models of planet formation, early evolution, and star-planet interaction. however, the intense magnetic activity of the host star makes measuring the masses of the planets via the radial velo... | one year of au mic with harps - i. measuring the masses of the two transiting planets |
although the main goal of the transiting exoplanet survey satellite (tess) is to search for new transiting exoplanets, its data can also be used to study already-known systems in further detail. the tess bandpass is particularly interesting to study the limb-darkening effect of the stellar host that is imprinted in tra... | empirical limb-darkening coefficients and transit parameters of known exoplanets from tess |
we apply the theory of radiative torque (rat) alignment for studying protoplanetary disks around a t-tauri star and perform 3d radiative transfer calculations to provide the expected maps of polarized radiation to be compared with observations, such as with alma. we revisit the issue of grain alignment for large grains... | radiative grain alignment in protoplanetary disks: implications for polarimetric observations |
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