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advancing technology in near-infrared instrumentation and dedicated planetary telescope facilities have enabled nearly two decades of reconnoitering the spectral properties for near-earth objects (neos). we report measured spectral properties for more than 1000 neos, representing >5% of the currently discovered popu... | compositional distributions and evolutionary processes for the near-earth object population: results from the mit-hawaii near-earth object spectroscopic survey (mithneos) |
the mass-period or radius-period distribution of close-in exoplanets shows a paucity of intermediate mass/size (sub-jovian) planets with periods ≲3 d. we show that this sub-jovian desert can be explained by the photoevaporation of highly irradiated sub-neptunes and the tidal disruption barrier for gas giants undergoing... | photoevaporation and high-eccentricity migration created the sub-jovian desert |
land free of direct anthropogenic disturbance is considered essential for achieving biodiversity conservation outcomes but is rapidly eroding. in response, many nations are increasing their protected area (pa) estates, but little consideration is given to the context of the surrounding landscape. this is despite the fa... | just ten percent of the global terrestrial protected area network is structurally connected via intact land |
present-day venus is an inhospitable place with surface temperatures approaching 750 k and an atmosphere 90 times as thick as earth's. billions of years ago the picture may have been very different. we have created a suite of 3-d climate simulations using topographic data from the magellan mission, solar spectral irrad... | was venus the first habitable world of our solar system? |
we measure dynamical masses for five objects—three ultracool dwarfs, one low-mass star, and one white dwarf—by fitting orbits to a combination of the hipparcos-gaia catalog of accelerations, literature radial velocities, and relative astrometry. our approach provides precise masses without any assumptions about the pri... | precise dynamical masses of directly imaged companions from relative astrometry, radial velocities, and hipparcos-gaia dr2 accelerations |
we present results from high-resolution, optical to near-ir imaging of host stars of kepler objects of interest (kois), identified in the original kepler field. part of the data were obtained under the kepler imaging follow-up observation program over six years (2009-2015). almost 90% of stars that are hosts to planet ... | the kepler follow-up observation program. i. a catalog of companions to kepler stars from high-resolution imaging |
volcanic degassing of planetary interiors has important implications for their corresponding atmospheres. the oxidation state of rocky interiors affects the volatile partitioning during mantle melting and subsequent volatile speciation near the surface. here we show that the mantle redox state is central to the chemica... | mantle redox state drives outgassing chemistry and atmospheric composition of rocky planets |
the fault diagnosis of planetary gearboxes is crucial to reduce the maintenance costs and economic losses. this paper proposes a novel fault diagnosis method based on adaptive multi-scale morphological filter (ammf) and modified hierarchical permutation entropy (mhpe) to identify the different health conditions of plan... | a fault diagnosis scheme for planetary gearboxes using adaptive multi-scale morphology filter and modified hierarchical permutation entropy |
the matter in extreme conditions end station at the linac coherent light source (lcls) is a new tool enabling accurate pump-probe measurements for studying the physical properties of matter in the high-energy density (hed) physics regime. this instrument combines the world’s brightest x-ray source, the lcls x-ray beam,... | matter under extreme conditions experiments at the linac coherent light source |
protoplanetary disks (ppds) are believed to accrete onto their central t tauri star because of magnetic stresses. recently published shearing box simulations indicate that ohmic resistivity, ambipolar diffusion (ad) and the hall effect all play important roles in disk evolution. in the presence of a vertical magnetic f... | global simulations of protoplanetary disks with ohmic resistivity and ambipolar diffusion |
the size distribution of asteroids and kuiper belt objects in the solar system is difficult to reconcile with a bottom-up formation scenario due to the observed scarcity of objects smaller than ~100 km in size. instead, planetesimals appear to form top-down, with large 100-1000 km bodies forming from the rapid gravitat... | how to form planetesimals from mm-sized chondrules and chondrule aggregates |
we used infrared data from the lunar reconnaissance orbiter (lro) diviner lunar radiometer experiment to globally map thermophysical properties of the moon's regolith fines layer. thermal conductivity varies from 7.4 × 10-4 w m-1 k-1 at the surface to 3.4 × 10-3 w m-1 k-1 at depths of 1 m, given density values of 1,100... | global regolith thermophysical properties of the moon from the diviner lunar radiometer experiment |
we present a new method to constrain the grain size in protoplanetary disks with polarization observations at millimeter wavelengths. if dust grains are grown to the size comparable to the wavelengths, the dust grains are expected to have a large scattering opacity, and thus the continuum emission is expected to be pol... | millimeter-wave polarization of protoplanetary disks due to dust scattering |
how much of earth's compositional variation dates to processes that occurred during planet formation remains an unanswered question. high-precision tungsten isotopic data from rocks from two large igneous provinces, the north atlantic igneous province and the ontong java plateau, reveal preservation to the phanerozoic ... | preservation of earth-forming events in the tungsten isotopic composition of modern flood basalts |
in this chapter, we review the breakthrough progress that has been made in the field of high-resolution, high-contrast optical and near-infrared imaging of planet-forming disks. these advancements include the direct detection of protoplanets embedded in disks, and derived limits on planetary masses in others. morpholog... | optical and near-infrared view of planet-forming disks and protoplanets |
we present the sixth catalog of kepler candidate planets based on nearly four years of high precision photometry. this catalog builds on the legacy of previous catalogs released by the kepler project and includes 1493 new kepler objects of interest (kois) of which 554 are planet candidates, and 131 of these candidates ... | planetary candidates observed by kepler. vi. planet sample from q1--q16 (47 months) |
the elemental compositions of hot jupiters are informative relics of planet formation that can help us answer long-standing questions regarding the origin and formation of giant planets. here, i present the main conclusions from a comprehensive atmospheric retrieval survey of eight hot jupiters with detectable molecula... | strict upper limits on the carbon-to-oxygen ratios of eight hot jupiters from self-consistent atmospheric retrieval |
we present electron densities n e in the interstellar medium (ism) of star-forming galaxies at z = 4-9 observed by the jwst/nirspec glass, early release observations, and ceers programs. we carefully evaluate the line-spread functions of the nirspec instrument as a function of wavelength with the calibration data of a ... | redshift evolution of electron density in the interstellar medium at z 0-9 uncovered with jwst/nirspec spectra and line-spread function determinations |
this paper presents an overview of spirou, the new-generation near-infrared spectropolarimeter/precision velocimeter recently installed on the 3.6-m canada-france-hawaii telescope (cfht). starting from the two main science goals, i.e., the quest for planetary systems around nearby m dwarfs and the study of magnetized s... | spirou: nir velocimetry and spectropolarimetry at the cfht |
giant exoplanets orbiting close to their host stars have high temperatures because of the immense amount of stellar irradiation that they receive. the extreme energy input leads to the expansion of the atmosphere and the escape of neutral hydrogen1-3. an intriguing case among the hot giant planets is kelt-9b, an exopla... | an extended hydrogen envelope of the extremely hot giant exoplanet kelt-9b |
context. recent observational findings have suggested a positive correlation between the occurrence rates of inner super-earths and outer giant planets. these results raise the question of whether this trend can be reproduced and explained by planet formation theory.aims: here, we investigate the properties of inner su... | the new generation planetary population synthesis (ngpps). iii. warm super-earths and cold jupiters: a weak occurrence correlation, but with a strong architecture-composition link |
the mass of a star is the most fundamental parameter for its structure, evolution, and final fate. it is particularly important for any kind of stellar archaeology and characterization of exoplanets. there exist a variety of methods in astronomy to estimate or determine it. in this review we present a significant numbe... | weighing stars from birth to death: mass determination methods across the hrd |
observational evidence for escaping exoplanet atmospheres has been obtained for a few exoplanets to date. it comes from strong transit signals detected in the ultraviolet, most notably in the wings of the hydrogen lyα (lyα) line. however, the core of the lyα line is often heavily affected by interstellar absorption and... | a new window into escaping exoplanet atmospheres: 10830 å line of helium |
we present k2sc (k2 systematics correction), a python pipeline to model instrumental systematics and astrophysical variability in light curves from the k2 mission. k2sc uses gaussian process regression to model position-dependent systematics and time-dependent variability simultaneously, enabling the user to remove bot... | k2sc: flexible systematics correction and detrending of k2 light curves using gaussian process regression |
solar system planets move on almost circular orbits. in strong contrast, many massive gas giant exoplanets travel on highly elliptical orbits, whereas the shape of the orbits of smaller, more terrestrial, exoplanets remained largely elusive. knowing the eccentricity distribution in systems of small planets would be imp... | eccentricity from transit photometry: small planets in kepler multi-planet systems have low eccentricities |
the compositions of stars are a critical diagnostic tool for many topics in astronomy such as the evolution of our galaxy, the formation of planets, and the uniqueness of the sun. previous spectroscopic measurements indicate a large intrinsic variation in the elemental abundance patterns of stars with similar overall m... | the chemical homogeneity of sun-like stars in the solar neighborhood |
a large planet orbiting a star in a protoplanetary disk opens a density gap along its orbit due to the strong disk-planet interaction and migrates with the gap in the disk. it is expected that in the ideal case, a gap-opening planet migrates at the viscous drift speed, which is referred to as type ii migration. however... | radial migration of gap-opening planets in protoplanetary disks. i. the case of a single planet |
there is a growing appreciation that the environmental conditions that we call space weather impact the technological infrastructure that powers the coupled economies around the world. with that comes the need to better shield society against space weather by improving forecasts, environmental specifications, and infra... | understanding space weather to shield society: a global road map for 2015-2025 commissioned by cospar and ilws |
we present scattered light images of the tw hya disk performed with the spectro-polarimetric high-contrast exoplanet research instrument in polarimetric differential imaging mode at 0.63, 0.79, 1.24, and 1.62 μm. we also present h2/h3-band angular differential imaging (adi) observations. three distinct radial depressio... | three radial gaps in the disk of tw hydrae imaged with sphere |
the dynamic activity of the sun—sustained by a magnetohydrodynamic dynamo mechanism working in its interior—modulates the electromagnetic, particulate, and radiative environment in space. while solar activity variations on short timescale create space weather, slow long-term modulation forms the basis of space climate.... | progress in solar cycle predictions: sunspot cycles 24-25 in perspective |
we present allesfitter, a public and open-source python software for flexible and robust inference of stars and exoplanets given photometric and radial velocity data. allesfitter offers a rich selection of orbital and transit/eclipse models, accommodating multiple exoplanets, multistar systems, transit-timing variation... | allesfitter: flexible star and exoplanet inference from photometry and radial velocity |
constellations of cubesats are emerging as a novel observational resource with the potential to overcome the spatiotemporal constraints of conventional single-sensor satellite missions. with a constellation of more than 170 active cubesats, planet has realized daily global imaging in the rgb and near-infrared (nir) at ... | daily retrieval of ndvi and lai at 3 m resolution via the fusion of cubesat, landsat, and modis data |
the conduction of heat through minerals and melts at extreme pressures and temperatures is of central importance to the evolution and dynamics of planets. in the cooling earth’s core, the thermal conductivity of iron alloys defines the adiabatic heat flux and therefore the thermal and compositional energy available to ... | direct measurement of thermal conductivity in solid iron at planetary core conditions |
satellite-based rainfall estimates over land have great potential for a wide range of applications, but their validation is challenging due to the scarcity of ground-based observations of rainfall in many areas of the planet. recent studies have suggested the use of triple collocation (tc) to characterize uncertainties... | an assessment of the performance of global rainfall estimates without ground-based observations |
we present a survey at subarcsecond resolution of the 340 ghz dust continuum emission from 50 nearby protoplanetary disks, based on new and archival observations with the submillimeter array. the observed visibility data were modeled with a simple prescription for the radial surface brightness profile. the results were... | a millimeter continuum size-luminosity relationship for protoplanetary disks |
comparing compositional models of the terrestrial planets provides insights into physicochemical processes that produced planet-scale similarities and differences. the widely accepted compositional model for mars assumes mn and more refractory elements are in ci chondrite proportions in the planet, including fe, mg, an... | the composition of mars |
the early earth’s environment is controversial. climatic estimates range from hot to glacial, and inferred marine ph spans strongly alkaline to acidic. better understanding of early climate and ocean chemistry would improve our knowledge of the origin of life and its coevolution with the environment. here, we use a geo... | constraining the climate and ocean ph of the early earth with a geological carbon cycle model |
we report the discovery of a white dwarf exhibiting deep, irregularly shaped transits, indicative of circumstellar planetary debris. using zwicky transient facility dr2 photometry of ztf j013906.17+524536.89 and follow-up observations from the las cumbres observatory, we identify multiple transit events that recur ever... | a white dwarf with transiting circumstellar material far outside the roche limit |
planet-disk interactions, where an embedded massive body interacts gravitationally with the protoplanetary disk it was formed in, can play an important role in reshaping both the disk and the orbit of the planet. spiral density waves are launched into the disk by the planet, which, if they are strong enough, can lead t... | planet-disk interactions and orbital evolution |
the past 5 years have dramatically changed our view of the disks of gas and dust around young stars. observations with the atacama large millimeter/submillimeter array (alma) and extreme adaptive optics systems have revealed that disks are dynamical systems. most disks contain resolved structures, both in gas and dust,... | kinematic structures in planet-forming disks |
the central molecular zone (cmz) is a ring-like accumulation of molecular gas in the innermost few hundred parsecs of the milky way, generated by the inward transport of matter driven by the galactic bar. the cmz is the most extreme star-forming environment in the galaxy. the unique combination of large-scale dynamics ... | star formation in the central molecular zone of the milky way |
the deep atmosphere venus investigation of noble gases, chemistry, and imaging (davinci) mission described herein has been selected for flight to venus as part of the nasa discovery program. davinci will be the first mission to venus to incorporate science-driven flybys and an instrumented descent sphere into a unified... | revealing the mysteries of venus: the davinci mission |
this report continues the practice where the iau working group on cartographic coordinates and rotational elements revises recommendations regarding those topics for the planets, satellites, minor planets, and comets approximately every 3 years. the working group has now become a "functional working group" of the iau, ... | report of the iau working group on cartographic coordinates and rotational elements: 2015 |
water ice is one of the most abundant materials in dense molecular clouds and in the outer reaches of protoplanetary disks. in contrast to other materials (e.g., silicates), water ice is assumed to be stickier due to its higher specific surface energy, leading to faster or more efficient growth in mutual collisions. ho... | the stickiness of micrometer-sized water-ice particles |
context. atmospheric properties of exoplanets can be constrained with transit spectroscopy. at low spectral resolution, this technique is limited by the presence of clouds. the signature of atomic sodium (na i), known to be present above the clouds, is a powerful probe of the upper atmosphere, where it can be best dete... | spectrally resolved detection of sodium in the atmosphere of hd 189733b with the harps spectrograph |
young exoplanets are snapshots of the planetary evolution process. planets that orbit stars in young associations are particularly important because the age of the planetary system is well constrained. we present the discovery of a transiting planet larger than neptune but smaller than saturn in the 45 myr tucana-horol... | tess hunt for young and maturing exoplanets (thyme): a planet in the 45 myr tucana-horologium association |
using new data from the k2 mission, we show that wasp-47, a previously known hot jupiter host, also hosts two additional transiting planets: a neptune-sized outer planet and a super-earth inner companion. we measure planetary properties from the k2 light curve and detect transit timing variations (ttvs), confirming the... | wasp-47: a hot jupiter system with two additional planets discovered by k2 |
earth has had oceans for nearly four billion years1 and mars had lakes and rivers 3.5-3.8 billion years ago2. however, it is still unknown whether water has ever condensed on the surface of venus3,4 because the planet—now completely dry5—has undergone global resurfacing events that obscure most of its history6,7. the c... | day-night cloud asymmetry prevents early oceans on venus but not on earth |
recent observations of extrasolar gas giants suggest super-stellar c/o ratios in planetary atmospheres, while interior models of observed extrasolar giant planets additionally suggest high heavy element contents. furthermore, recent observations of protoplanetary disks revealed super-solar c/h ratios, which are explain... | how drifting and evaporating pebbles shape giant planets. i. heavy element content and atmospheric c/o |
since the discovery of the multiring structure of the hl tau disk, alma data suggest that the dust continuum emission of many, if not all, protoplanetary disks consists of rings and gaps, no matter their spectral type or age. the origin of these gaps so far remains unclear. we present a sample study of 16 disks with mu... | protoplanetary disk rings and gaps across ages and luminosities |
we present an overview of the sample of northern hemisphere white dwarfs within 40 pc of the sun detected from gaia data release 2 (dr2). we find that 521 sources are spectroscopically confirmed degenerate stars, 111 of which were first identified as white dwarf candidates from gaia dr2 and followed up recently with th... | gaia white dwarfs within 40 pc ii: the volume-limited northern hemisphere sample |
the atmospheric northward energy transport plays a crucial role for the arctic climate; this transport brings to the arctic an amount of energy comparable to that provided directly by the sun. the transport is accomplished by atmospheric waves-for instance large-scale planetary waves and meso-scale cyclones-and the zon... | arctic amplification enhanced by latent energy transport of atmospheric planetary waves |
we present a study on the effect of undetected stellar companions on the derived planetary radii for kepler objects of interest (kois). the current production of the koi list assumes that each koi is a single star. not accounting for stellar multiplicity statistically biases the planets toward smaller radii. the bias t... | understanding the effects of stellar multiplicity on the derived planet radii from transit surveys: implications for kepler, k2, and tess |
binary interactions dominate the evolution of massive stars, but their role is less clear for low- and intermediate-mass stars. the evolution of a spherical wind from an asymptotic giant branch (agb) star into a nonspherical planetary nebula (pn) could be due to binary interactions. we observed a sample of agb stars wi... | (sub)stellar companions shape the winds of evolved stars |
pressure-driven shock waves in solid materials can cause extreme damage and deformation. understanding this deformation and the associated defects that are created in the material is crucial in the study of a wide range of phenomena, including planetary formation and asteroid impact sites, the formation of interstellar... | in situ x-ray diffraction measurement of shock-wave-driven twinning and lattice dynamics |
recognizing whether a planet can support life is a primary goal of future exoplanet spectral characterization missions, but past research on habitability assessment has largely ignored the vastly different conditions that have existed in our planet's long habitable history. this study presents simulations of a habitabl... | the pale orange dot: the spectrum and habitability of hazy archean earth |
we present an update to the everest k2 pipeline that addresses various limitations in the previous version and improves the photometric precision of the light curves. we develop a fast regularization scheme for pixel-level decorrelation (pld) and adapt the algorithm to include the pld vectors of other stars to enhance ... | an update to the everest k2 pipeline: short cadence, saturated stars, and kepler-like photometry down to kp = 15 |
the isotopic composition of meteorites and terrestrial planets holds important clues about the earliest history of the solar system and the processes of planet formation. recent work has shown that meteorites exhibit a fundamental isotopic dichotomy between non-carbonaceous (nc) and carbonaceous (cc) groups, which most... | the great isotopic dichotomy of the early solar system |
ultracool dwarfs (ucd; teff < ∼3000 k) cool to settle on the main sequence after ∼1 gyr. for brown dwarfs, this cooling never stops. their habitable zones (hz) thus sweeps inward at least during the first gyr of their lives. assuming they possess water, planets found in the hz of ucds have experienced a runaway gree... | water loss from terrestrial planets orbiting ultracool dwarfs: implications for the planets of trappist-1 |
giant exoplanets orbiting very close to their parent star (hot jupiters) are subject to tidal forces expected to synchronize their rotational and orbital periods on short timescales (tidal locking). however, spin rotation has never been measured directly for hot jupiters. furthermore, their atmospheres can show equator... | rotation and winds of exoplanet hd 189733 b measured with high-dispersion transmission spectroscopy |
we present a consistent optimal estimation retrieval analysis of 10 hot jupiter exoplanets, each with transmission spectral data spanning the visible to near-infrared wavelength range. using the nemesis radiative transfer and retrieval tool, we calculate a range of possible atmospheric states for wasp-6b, wasp-12b, was... | a consistent retrieval analysis of 10 hot jupiters observed in transmission |
nasa's plans for space exploration include a return to the moon to stay—boots back on the lunar surface with an orbital outpost. this station will be a launch point for voyages to destinations further away in our solar system, including journeys to the red planet mars. to ensure success of these missions, health and pe... | red risks for a journey to the red planet: the highest priority human health risks for a mission to mars |
flow in a stably stratified environment is characterized by anisotropic and intermittent turbulence and wavelike motions of varying amplitudes and periods. understanding turbulence intermittency and wave-turbulence interactions in a stably stratified flow remains a challenging issue in geosciences including planetary a... | review of wave-turbulence interactions in the stable atmospheric boundary layer |
during the period from approximately 150 to 35 million years ago, the cretaceous-paleocene-eocene (cpe), the earth was in a "greenhouse" state with little or no ice at either pole. it was also a period of considerable global change, from the warmest periods of the mid-cretaceous, to the threshold of icehouse conditions... | palaeogeographic controls on climate and proxy interpretation |
bed load sediment transport, in which wind or water flowing over a bed of sediment causes grains to roll or hop along the bed, is a critically important mechanism in contexts ranging from river restoration1 to planetary exploration2. despite its widespread occurrence, predictions of bed load sediment flux are notorious... | grain shape effects in bed load sediment transport |
two >130-meter-diameter impact craters formed on mars during the later half of 2021. these are the two largest fresh impact craters discovered by the mars reconnaissance orbiter since operations started 16 years ago. the impacts created two of the largest seismic events (magnitudes greater than 4) recorded by insigh... | largest recent impact craters on mars: orbital imaging and surface seismic co-investigation |
observations of planet earth from space are a critical resource for science and society. satellite measurements represent very large investments and united states (us) agencies organize their effort to maximize the return on that investment. the us national research council conducts a survey of earth science and applic... | designing an observing system to study the surface biology and geology (sbg) of the earth in the 2020s |
deep inside planets, extreme density, pressure, and temperature strongly modify the properties of the constituent materials. in particular, how much heat solids can sustain before melting under pressure is key to determining a planet’s internal structure and evolution. we report laser-driven shock experiments on fused ... | shock compression of stishovite and melting of silica at planetary interior conditions |
symmetry-breaking transitions associated with the buckling and folding of curved multilayered surfaces—which are common to a wide range of systems and processes such as embryogenesis, tissue differentiation and structure formation in heterogeneous thin films or on planetary surfaces—have been characterized experimental... | curvature-induced symmetry breaking determines elastic surface patterns |
the tibetan plateau and its surrounding mountains have an average elevation of 4,400 m and a glaciated area of ∼100,000 km2 giving it the name "third pole (tp) region". the tp is the headwater of many major rivers in asia that provide fresh water to hundreds of millions of people. climate change is altering the energy ... | towards ensemble-based kilometer-scale climate simulations over the third pole region |
intense lasers interacting with dense targets accelerate relativistic electron beams, which transport part of the laser energy into the target depth. however, the overall laser-to-target energy coupling efficiency is impaired by the large divergence of the electron beam, intrinsic to the laser-plasma interaction. here ... | guiding of relativistic electron beams in dense matter by laser-driven magnetostatic fields |
an accurate description of the center-to-limb variation (clv) of stellar spectra is becoming an increasingly critical factor in both stellar and exoplanet characterization. in particular, the clv of spectral lines is extremely challenging as its characterization requires highly detailed knowledge of the stellar physica... | center-to-limb variation of spectral lines and their effect on full-disk observations |
the jwst disk infrared spectral chemistry survey (jdiscs) aims to understand the evolution of the chemistry of inner protoplanetary disks using the mid-infrared instrument (miri) on the james webb space telescope (jwst). with a growing sample of >30 disks, the survey implements a custom method to calibrate the miri ... | high-contrast jwst-miri spectroscopy of planet-forming disks for the jdisc survey |
wasp-12b is a transiting hot jupiter on a 1.09 day orbit around a late-f star. since the planet’s discovery in 2008, the time interval between transits has been decreasing by 29 ± 2 ms yr-1. this is a possible sign of orbital decay, although the previously available data left open the possibility that the planet’s orbi... | the orbit of wasp-12b is decaying |
axisymmetric dust rings are a ubiquitous feature of young protoplanetary disks. these rings are likely caused by pressure bumps in the gas profile; a small bump can induce a traffic-jam-like pattern in the dust density, while a large bump may halt radial dust drift entirely. the resulting increase in dust concentration... | protoplanetary disk rings as sites for planetesimal formation |
circumbinary accretion occurs throughout the universe, from the formation of stars and planets to the aftermath of major galactic mergers. we present an extensive investigation of circumbinary accretion disks, studying circular binaries with mass ratios ($q\equiv m_2/m_1$) from 0.01 to 1 and at each mass ratio probing ... | the evolution of accreting binaries: from brown dwarfs to supermassive black holes |
the presence of an atmosphere over sufficiently long timescales is widely perceived as one of the most prominent criteria associated with planetary surface habitability. we address the crucial question of whether the seven earth-sized planets transiting the recently discovered ultracool dwarf star trappist-1 are capabl... | atmospheric escape from the trappist-1 planets and implications for habitability |
the origins space telescope (origins) traces our cosmic history, from the formation of the first galaxies and the rise of metals to the development of habitable worlds and present-day life. origins does this through exquisite sensitivity to infrared radiation from ions, atoms, molecules, dust, water vapor and ice, and ... | origins space telescope mission concept study report |
context. the discovery of proxima b marked one of the most important milestones in exoplanetary science in recent years. yet the limited precision of the available radial velocity data and the difficulty in modelling the stellar activity calls for a confirmation of the earth-mass planet.aims: we aim to confirm the pres... | revisiting proxima with espresso |
we present the discovery and validation of a three-planet system orbiting the nearby (31.1 pc) m2 dwarf star toi-700 (tic 150428135). toi-700 lies in the tess continuous viewing zone in the southern ecliptic hemisphere; observations spanning 11 sectors reveal three planets with radii ranging from 1 r⊕ to 2.6 r⊕ and orb... | the first habitable-zone earth-sized planet from tess. i. validation of the toi-700 system |
the characterization of objects that have best preserved the mineralogical and molecular phases formed in the earliest stages of the solar system evolution is key to understanding the processes that led to the formation of the planets in their diversity. the hayabusa2 mission of the japan aerospace exploration agency h... | first compositional analysis of ryugu samples by the micromega hyperspectral microscope |
the james webb space telescope (jwst) is a large, infrared space telescope that has recently started its science program which will enable breakthroughs in astrophysics and planetary science. notably, jwst will provide the very first observations of the earliest luminous objects in the universe and start a new era of e... | the james webb space telescope mission: optical telescope element design, development, and performance |
(abridged) we investigate the impact of radiative feedback from massive stars on their natal cloud and focus on the transition from the hii region to the atomic pdr (crossing the ionisation front (if)), and the subsequent transition to the molecular pdr (crossing the dissociation front (df)). we use high-resolution nea... | pdrs4all iii: jwst's nir spectroscopic view of the orion bar |
we present an analysis of atacama large millimeter/submillimeter array 1.25 mm continuum observations of spiral structures in three protoplanetary disks from the disk substructures at high angular resolution project. the disks around elias 27, im lup, and waoph 6 were observed at a resolution of ∼40-60 mas (∼6-7 au). a... | the disk substructures at high angular resolution project (dsharp). iii. spiral structures in the millimeter continuum of the elias 27, im lup, and waoph 6 disks |
aerocapture is the technique of using planetary atmospheres to decelerate a spacecraft in a single pass to achieve nearly fuel-free orbit insertion. aerocapture has been extensively studied since the 1980s but has never been flown yet. the entry conditions encountered during aerocapture are strongly destination depende... | aerocapture design reference missions for solar system exploration: from venus to neptune |
the composition of giant planets is imprinted by their migration history and the compositional structure of their hosting disks. studies in recent literature have investigated how the abundances of c and o can constrain the formation pathways of giant planets forming within few tens of au from a star. new alma observat... | tracing the formation history of giant planets in protoplanetary disks with carbon, oxygen, nitrogen, and sulfur |
understanding how marine low clouds and their radiative effects respond to changing meteorological conditions is crucial to constrain low-cloud feedbacks to greenhouse warming and internal climate variability. in this study, we use observations to quantify the low-cloud radiative response to meteorological perturbation... | observed sensitivity of low-cloud radiative effects to meteorological perturbations over the global oceans |
bepicolombo is a joint mission between the european space agency, esa, and the japanese aerospace exploration agency, jaxa, to perform a comprehensive exploration of mercury. launched on 20th october 2018 from the european spaceport in kourou, french guiana, the spacecraft is now en route to mercury. | bepicolombo - mission overview and science goals |
human-induced climate change impacts the hydrological cycle and thus the availability of water resources. however, previous assessments of observed warming-induced changes in dryness have not excluded natural climate variability and show conflicting results due to uncertainties in our understanding of the response of e... | observed changes in dry-season water availability attributed to human-induced climate change |
giant planets migrate though the protoplanetary disc as they grow their solid core and attract their gaseous envelope. previously, we have studied the growth and migration of an isolated planet in an evolving disc. here, we generalise such models to include the mutual gravitational interaction between a high number of ... | formation of planetary systems by pebble accretion and migration: growth of gas giants |
the advent of global precipitation data sets with increasing temporal span has made it possible to use them for validating climate models. in order to fulfill the requirement of global coverage, existing products integrate satellite-derived retrievals from many sensors with direct ground observations (gauges, disdromet... | global precipitation measurements for validating climate models |
the third data release of gaia was the first to include orbital solutions assuming non-single stars. here, we apply the astrometric triage technique of shahaf et al. 2019 to identify binary star systems with companions that are not single main-sequence stars. gaia's synthetic photometry of these binaries is used to dis... | triage of the gaia dr3 astrometric orbits. ii. a census of white dwarfs |
the large sky area multi-object fiber spectroscopic telescope (lamost), also known as the guoshoujing telescope, is a major national scientific facility for astronomical research located in xinglong, china. beginning with a pilot survey in 2011, lamost has been surveying the night sky for more than 10 years. the lamost... | overview of the lamost survey in the first decade |
over the past decade, observations of giant exoplanets (jupiter-size) have provided key insights into their atmospheres, but the properties of lower-mass exoplanets (sub-neptune) remain largely unconstrained because of the challenges of observing small planets. numerous efforts to observe the spectra of super-earths—ex... | a map of the large day-night temperature gradient of a super-earth exoplanet |
we use more than 2 years of magnetic data from the swarm mission, and monthly means from 160 ground observatories as available in march 2016, to update the chaos time-dependent geomagnetic field model. the new model, chaos-6, provides information on time variations of the core-generated part of the earth's magnetic fie... | recent geomagnetic secular variation from swarm and ground observatories as estimated in the chaos-6 geomagnetic field model |
throughout earth's history, redox transformations in sedimentary environments have occurred through chemical processes (abiotic pathways) or via the activity of living microorganisms (biotic pathway). tools able to discriminate between these two mechanisms are of major interest, as they would contribute significantly t... | uranium isotopes fingerprint biotic reduction |
atmospheric aerosols have been found to influence the development of planetary boundary layer (pbl) and hence to enhance haze pollution in megacities. previous works on aerosol-pbl interaction were mainly based on model simulation for short-term cases; so far, there is a lack of long-term observational evidences. in th... | impact of aerosol-pbl interaction on haze pollution: multiyear observational evidences in north china |
this paper presents new high angular resolution alma 1.3 mm dust continuum observations of the protoplanetary system as 209 in the ophiuchus star forming region. the dust continuum emission is characterized by a main central core and two prominent rings at r = 75 au and r = 130 au intervaled by two gaps at r = 62 au an... | alma continuum observations of the protoplanetary disk as 209. evidence of multiple gaps opened by a single planet |
we present three transit observations of hd 189733 b obtained with the high-resolution spectrograph carmenes at calar alto. a strong absorption signal is detected in the near-infrared he i triplet at 10830 å in all three transits. during mid-transit, the mean absorption level is 0.88 ± 0.04% measured in a ±10 km s-1 ra... | detection of he i λ10830 å absorption on hd 189733 b with carmenes high-resolution transmission spectroscopy |
in situ research of cometary chemistry began when measurements from the giotto mission at comet 1p/halley revealed the presence of complex organics in the coma. new telescopes and space missions have provided detailed remote and in situ measurements of the composition of cometary volatiles. recently, the rosetta missio... | cometary chemistry and the origin of icy solar system bodies: the view after rosetta |
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