abstract stringlengths 3 192k | title stringlengths 4 857 |
|---|---|
jupiter's atmosphere is enriched in c, n, s, p, ar, kr, and xe with respect to solar abundances by a factor of ∼3. gas giant envelopes are mainly enriched through the dissolution of solids in the atmosphere, and this constant enrichment factor is puzzling since several of the above elements are not expected to have bee... | jupiter's composition suggests its core assembled exterior to the n2 snowline |
the atmosphere of a brown dwarf or extrasolar giant planet controls the spectrum of radiation emitted by the object and regulates its cooling over time. although the study of these atmospheres has been informed by decades of experience modeling stellar and planetary atmospheres, the distinctive characteristics of these... | on the cool side: modeling the atmospheres of brown dwarfs and giant planets |
the origin of life on earth seems to demand a highly reduced early atmosphere, rich in ch4, h2, and nh3, but geological evidence suggests that earth's mantle has always been relatively oxidized and its emissions dominated by co2, h2o, and n2. the paradox can be resolved by exploiting the reducing power inherent in the ... | creation and evolution of impact-generated reduced atmospheres of early earth |
context. probing the evaporation of exoplanet atmospheres is key to understanding the formation and evolution of exoplanetary systems. the main tracer of evaporation in the uv is the lyman-α transition, which can reveal extended exospheres of neutral hydrogen. recently, the near-infrared (nir) metastable helium triplet... | high-resolution confirmation of an extended helium atmosphere around wasp-107b |
the present-day envelope of gaseous planets is a relic of how these giant planets originated and evolved. measuring their elemental composition therefore presents a powerful opportunity to answer long-standing questions regarding planet formation. obtaining precise observational constraints on the elemental inventory o... | where is the water? jupiter-like c/h ratio but strong h2o depletion found on τ boötis b using spirou |
earth grew through collisions with moon-sized to mars-sized planetary embryos from the inner solar system, but it also accreted material from greater heliocentric distances1,2, including carbonaceous chondrite-like bodies, the likely source of earth's water and highly volatile species3,4. understanding when and how thi... | molybdenum isotopic evidence for the late accretion of outer solar system material to earth |
aims: to date, infrared interferometry at best achieved contrast ratios of a few times 10-4 on bright targets. gravity, with its dual-field mode, is now capable of high contrast observations, enabling the direct observation of exoplanets. we demonstrate the technique on hr 8799, a young planetary system composed of fou... | first direct detection of an exoplanet by optical interferometry. astrometry and k-band spectroscopy of hr 8799 e |
isotopic variations usually follow mass-dependent fractionation, meaning that the relative variations in isotopic ratios scale with the difference in mass of the isotopes involved (e.g., δ17o ≈ 0.5×δ18o). in detail, however, the mass dependence of isotopic variations is not always the same, and different natural proces... | mass fractionation laws, mass-independent effects, and isotopic anomalies |
a relation between the mass accretion rate onto the central young star and the mass of the surrounding protoplanetary disk has long been theoretically predicted and observationally sought. for the first time, we have accurately and homogeneously determined the photospheric parameters, mass accretion rate, and disk mass... | evidence for a correlation between mass accretion rates onto young stars and the mass of their protoplanetary disks |
we searched for superflares on solar-type stars using kepler data with 1-min sampling in order to detect superflares with a short duration. we found 187 superflares on 23 solar-type stars whose bolometric energy ranges from the order of 1032 to 1036 erg. some superflares show multiple peaks with the peak separation of ... | statistical properties of superflares on solar-type stars based on 1-min cadence data |
we present exoplanet occurrence rates estimated with approximate bayesian computation for planets with radii between 0.5 and 16 r⊕ and orbital periods between 0.78 and 400 days orbiting fgk dwarf stars. we base our results on an independent planet catalog compiled from our search of all ∼200,000 stars observed over the... | searching the entirety of kepler data. ii. occurrence rate estimates for fgk stars |
aims: we study the evolution of stellar rotation and wind properties for low-mass main-sequence stars. our aim is to use rotational evolution models to constrain the mass loss rates in stellar winds and to predict how their properties evolve with time on the main-sequence.methods: we construct a rotational evolution mo... | stellar winds on the main-sequence. ii. the evolution of rotation and winds |
using data taken with the keck planet finder spectrograph we calculate a host e(b-v) extinction of 0.031±0.006. | host extinction of sn2023ixf |
the magnitude and distribution of net primary production (npp) in the coastal ocean remains poorly constrained, particularly for shallow marine vegetation. here, using a compilation of in situ annual npp measurements across >400 sites in 72 geographic ecoregions, we provide global predictions of the productivity of ... | global seaweed productivity |
the outer solar system origins survey (ossos), a wide-field imaging program in 2013-2017 with the canada-france-hawaii telescope, surveyed 155 deg2 of sky to depths of mr= 24.1-25.2. we present 838 outer solar system discoveries that are entirely free of ephemeris bias. this increases the inventory of trans-neptunian o... | ossos. vii. 800+ trans-neptunian objects—the complete data release |
we confirm and characterize a close-in ({p}{{orb}} = 5.425 days), super-neptune sized ({5.04}-0.37+0.34 {r}\oplus ) planet transiting k2-33 (2mass j16101473-1919095), a late-type (m3) pre-main-sequence (11 myr old) star in the upper scorpius subgroup of the scorpius-centaurus ob association. the host star has the kinem... | zodiacal exoplanets in time (zeit). iii. a short-period planet orbiting a pre-main-sequence star in the upper scorpius ob association |
theories of the formation and early evolution of planetary systems postulate that planets are born in circumstellar disks, and undergo radial migration during and after dissipation of the dust and gas disk from which they formed. the precise ages of meteorites indicate that planetesimals—the building blocks of planets—... | a neptune-sized transiting planet closely orbiting a 5-10-million-year-old star |
high resolution transit spectroscopy has proven to be a reliable technique for the characterization of the chemical composition of exoplanet atmospheres. taking advantage of the broad spectral coverage of the carmenes spectrograph, we initiated a survey aimed at characterizing a broad range of planetary systems. here, ... | a he i upper atmosphere around the warm neptune gj 3470 b |
using current technology, gravitational microlensing is the only method that can measure planet masses over the full parameter space of planet and stellar-host masses and at a broad range of planet-host separations. i present a comprehensive program to transform the $\sim 150$ planet/host mass ratio measurements from t... | masada: from microlensing planet mass-ratio function to planet mass function |
to identify promising exoplanets for atmospheric characterization and to make the best use of observational data, a thorough understanding of their atmospheres is needed. three-dimensional general circulation models (gcms) are one of the most comprehensive tools available for this task and will be used to interpret obs... | the trappist-1 habitable atmosphere intercomparison (thai). ii. moist cases-the two waterworlds |
we present updated radial-velocity (rv) analyses of the au mic system. au mic is a young (22 myr) early-m dwarf known to host two transiting planets-pb~ 8.46 days, ${r}_{b}={4.38}_{-0.18}^{+0.18}\ {r}_{\oplus }$ , pc~ 18.86 days, ${r}_{c}={3.51}_{-0.16}^{+0.16}\ {r}_{\oplus }$ . with visible rvs from calar alto high-re... | diving beneath the sea of stellar activity: chromatic radial velocities of the young au mic planetary system |
capturing planets in the act of losing their atmospheres provides rare opportunities to probe their evolution history. this analysis has been enabled by observations of the helium triplet at 10,833 angstrom, but past studies have focused on the narrow time window right around the planet's optical transit. we monitored ... | giant tidal tails of helium escaping the hot jupiter hat-p-32 b |
the dependence of the mass accretion rate on the stellar properties is a key constraint for star formation and disk evolution studies. here we present a study of a sample of stars in the chamaeleon i star-forming region carried out using spectra taken with the eso vlt/x-shooter spectrograph. the sample is nearly comple... | x-shooter study of accretion in chamaeleon i. ii. a steeper increase of accretion with stellar mass for very low-mass stars? |
wide-field high-precision photometric surveys such as kepler have produced reams of data suitable for investigating stellar magnetic activity of cooler stars. starspot activity produces quasi-sinusoidal light curves whose phase and amplitude vary as active regions grow and decay over time. here we investigate, first, w... | a kepler study of starspot lifetimes with respect to light-curve amplitude and spectral type |
groundwater is by far the largest unfrozen freshwater resource on the planet. it plays a critical role as the bottom of the hydrologic cycle, redistributing water in the subsurface and supporting plants and surface water bodies. however, groundwater has historically been excluded or greatly simplified in global models.... | global groundwater modeling and monitoring: opportunities and challenges |
context. methods used to detect giant exoplanets can be broadly divided into two categories: indirect and direct. indirect methods are more sensitive to planets with a small orbital period, whereas direct detection is more sensitive to planets orbiting at a large distance from their host star. this dichotomy makes it d... | direct confirmation of the radial-velocity planet β pictoris c |
meteoroid impacts shape planetary surfaces by forming new craters and alter atmospheric composition. during atmospheric entry and impact on the ground, meteoroids excite transient acoustic and seismic waves. however, new crater formation and the associated impact-induced mechanical waves have yet to be observed jointly... | newly formed craters on mars located using seismic and acoustic wave data from insight |
climate change has emerged as an important issue ever to confront mankind. this concern emerges from the fact that our day-to-day activities are leading to impacts on the earth's atmosphere that has the potential to significantly alter the planet's shield and radiation balance. developing countries particularly whose i... | temperature and precipitation trends in kashmir valley, north western himalayas |
vertical wind shear (vws) is one of the key meteorological factors in modulating ground-level particulate matter with an aerodynamic diameter of 2.5 µm or less (pm2.5). due to the lack of high-resolution vertical wind measurements, how the vws affects ground-level pm2.5 remains highly debated. here we employed the wind... | vertica wind shear modulates particulate matter pollutions: a perspective from radar wind profiler observations in beijing, china |
it has long been recognized that earth and other differentiated planetary bodies are chemically fractionated compared to primitive, chondritic meteorites and, by inference, the primordial disk from which they formed. however, it is not known whether the notable volatile depletions of planetary bodies are a consequence ... | magnesium isotope evidence that accretional vapour loss shapes planetary compositions |
generative deep learning has sparked a new wave of super-resolution (sr) algorithms that enhance single images with impressive aesthetic results, albeit with imaginary details. multi-frame super-resolution (mfsr) offers a more grounded approach to the ill-posed problem, by conditioning on multiple low-resolution views.... | highres-net: recursive fusion for multi-frame super-resolution of satellite imagery |
low-mass stars show evidence of vigorous magnetic activity in the form of large flares and coronal mass ejections. such space weather events may have important ramifications for the habitability and observational fingerprints of exoplanetary atmospheres. here, using a suite of three-dimensional coupled chemistry-climat... | persistence of flare-driven atmospheric chemistry on rocky habitable zone worlds |
m dwarf stars are known for their vigorous flaring. this flaring could impact the climate of orbiting planets, making it important to characterize m dwarf flares at the short wavelengths that drive atmospheric chemistry and escape. we conducted a far-ultraviolet flare survey of six m dwarfs from the recent muscles (mea... | the muscles treasury survey. v. fuv flares on active and inactive m dwarfs |
limb darkening is fundamental in determining transit light-curve shapes, and is typically modelled by a variety of laws that parametrize the intensity profile of the star that is being transited. confronted with a transit light curve, some authors fix the parameters of these laws, the so-called limb darkening coefficie... | limb darkening and exoplanets: testing stellar model atmospheres and identifying biases in transit parameters |
sudden stratospheric warming (ssw) events have received increased attention since their impacts on the troposphere became evident recently. studies of ssw usually focus on polar stratospheric conditions; however, understanding the global impact of these events requires studying them from a wider perspective. case studi... | absorbing and reflecting sudden stratospheric warming events and their relationship with tropospheric circulation |
identifying unequivocal signs of life on mars is one of the most important objectives for sending missions to the red planet. here we report red stone, a 163-100 my alluvial fan-fan delta that formed under arid conditions in the atacama desert, rich in hematite and mudstones containing clays such as vermiculite and sme... | dark microbiome and extremely low organics in atacama fossil delta unveil mars life detection limits |
megacities are major sources of anthropogenic fossil fuel co2 (ffco2) emissions. the spatial extents of these large urban systems cover areas of 10 000 km2 or more with complex topography and changing landscapes. we present a high-resolution land-atmosphere modelling system for urban co2 emissions over the los angeles ... | los angeles megacity: a high-resolution land-atmosphere modelling system for urban co2 emissions |
primary production by marine phytoplankton is one of the largest fluxes of carbon on our planet. in the past few decades, considerable progress has been made in estimating global primary production at high spatial and temporal scales by combining in situ measurements of primary production with remote-sensing observatio... | primary production, an index of climate change in the ocean: satellite-based estimates over two decades |
i review the influence jets and the bubbles they inflate might have on their ambient gas as they operate through a negative jet feedback mechanism (jfm). i discuss astrophysical systems where jets are observed to influence the ambient gas, in many cases by inflating large, hot, and low-density bubbles, and systems wher... | the jet feedback mechanism (jfm) in stars, galaxies and clusters |
we provide a calculation of pan-starrs’ ability to detect objects similar to the interstellar object 1i/2017 u1 (hereafter ‘oumuamua), including the most detectable approach vectors and the effect of object size on detection efficiency. using our updated detection cross section, we infer an interstellar number density ... | interstellar interlopers: number density and origin of ‘oumuamua-like objects |
the hr 8799 system uniquely harbors four young super-jupiters whose orbits can provide insights into the system’s dynamical history and constrain the masses of the planets themselves. using the gemini planet imager, we obtained down to one milliarcsecond precision on the astrometry of these planets. we assessed four-pl... | dynamical constraints on the hr 8799 planets with gpi |
astronomical calculations reveal the solar system’s dynamical evolution, including its chaoticity, and represent the backbone of cyclostratigraphy and astrochronology. an absolute, fully calibrated astronomical time scale has hitherto been hampered beyond ~50 million years before the present (ma) because orbital calcul... | solar system chaos and the paleocene-eocene boundary age constrained by geology and astronomy |
we present a velocimetric and spectropolarimetric analysis of 27 observations of the 22-myr m1 star au microscopii (au mic) collected with the high-resolution yjhk (0.98-2.35 μm) spectropolarimeter spirou from 2019 september 18 to november 14. our radial velocity (rv) time-series exhibits activity-induced fluctuations ... | investigating the young au mic system with spirou: large-scale stellar magnetic field and close-in planet mass |
planetary rings are observed not only around giant planets1, but also around small bodies such as the centaur chariklo2 and the dwarf planet haumea3. up to now, all known dense rings were located close enough to their parent bodies, being inside the roche limit, where tidal forces prevent material with reasonable densi... | a dense ring of the trans-neptunian object quaoar outside its roche limit |
we present the confirmation of two new planets transiting the nearby mid-m dwarf ltt 3780 (tic 36724087, toi-732, v = 13.07, ks = 8.204, rs = 0.374 r⊙, ms = 0.401 m⊙, d = 22 pc). the two planet candidates are identified in a single transiting exoplanet survey satellite sector and validated with reconnaissance spectrosc... | a pair of tess planets spanning the radius valley around the nearby mid-m dwarf ltt 3780 |
prestellar cores represent the initial conditions in the process of star and planet formation. their low temperatures (<10 k) allow the formation of thick icy dust mantles, which will be partially preserved in future protoplanetary disks, ultimately affecting the chemical composition of planetary systems. previous o... | the central 1000 au of a prestellar core revealed with alma. ii. almost complete freeze-out |
the so-called lidov-kozai oscillation is very well known and applied to various problems in solar system dynamics. this mechanism makes the orbital inclination and eccentricity of the perturbed body in the circular restricted three-body system oscillate with a large amplitude under certain conditions. it is widely acce... | the lidov-kozai oscillation and hugo von zeipel |
we highlight that the anomalous orbits of trans-neptunian objects (tnos) and an excess in microlensing events in the 5-year optical gravitational lensing experiment data set can be simultaneously explained by a new population of astrophysical bodies with mass several times that of the earth (m⊕). we take these objects ... | what if planet 9 is a primordial black hole? |
we review the origin and evolution of the atmospheres of earth, venus and mars from the time when their accreting bodies were released from the protoplanetary disk a few million years after the origin of the sun. if the accreting planetary cores reached masses ≥ 0.5 m_earth before the gas in the disk disappeared, primo... | origin and evolution of the atmospheres of early venus, earth and mars |
martian moons exploration, mmx, is the new sample return mission planned by the japan aerospace exploration agency (jaxa) targeting the two martian moons with the scheduled launch in 2024 and return to the earth in 2029. the major scientific objectives of this mission are to determine the origin of phobos and deimos, t... | martian moons exploration mmx: sample return mission to phobos elucidating formation processes of habitable planets |
about half of all optical observations collected via spaceborne satellites are affected by haze or clouds. consequently, cloud coverage affects the remote sensing practitioner's capabilities of a continuous and seamless monitoring of our planet. this work addresses the challenge of optical satellite image reconstructio... | sen12ms-cr-ts: a remote-sensing data set for multimodal multitemporal cloud removal |
our planet is changing at paces never observed before. species extinction is happening at faster rates than ever, greatly exceeding the five mass extinctions in the fossil record. nevertheless, our lives are strongly based on services provided by ecosystems, thus the responses to global change of our natural heritage a... | complexity and stability of ecological networks: a review of the theory |
the extensive array of mid-20th century stratigraphic event signals associated with the 'great acceleration' enables precise and unambiguous recognition of the anthropocene as an epoch/series within the geological time scale. a mid-20th century inception is consistent with earth system science analysis in which the ant... | the proposed anthropocene epoch/series is underpinned by an extensive array of mid-20 th century stratigraphic event signals |
mars’ sedimentary rock record preserves information on geological (and potential astrobiological) processes that occurred on the planet billions of years ago. the curiosity rover is exploring the lower reaches of mount sharp, in gale crater on mars. a traverse from vera rubin ridge to glen torridon has allowed curiosit... | brine-driven destruction of clay minerals in gale crater, mars |
methane-producing microorganisms are thought to be among the earliest cellular life forms colonizing our planet, and are major contributors to the past and present global carbon cycle. currently, all methanogens belong to the archaeal domain of life, and there is compounding evidence for a variety of methanogenic metab... | hydrogenotrophic methanogenesis in archaeal phylum verstraetearchaeota reveals the shared ancestry of all methanogens |
accurate land use land cover (lulc) classification is vital for the sustainable management of natural resources and to learn how the landscape is changing due to climate. for accurate and efficient lulc classification, high-quality datasets and robust classification methods are required. with the increasing availabilit... | comparison of land use land cover classifiers using different satellite imagery and machine learning techniques |
we present a statistical analysis of the kepler m dwarf planet hosts, with a particular focus on the fractional number of systems hosting multiple transiting planets. we manufacture synthetic planetary systems within a range of planet multiplicity and mutual inclination for comparison to the kepler yield. similarly to ... | the kepler dichotomy among the m dwarfs: half of systems contain five or more coplanar planets |
current models of (exo)planet formation often rely on a large influx of so-called “pebbles” from the outer disk into the planet formation region. in this paper, we investigate how the formation/coagulation of pebbles in the cold outer regions of protoplanetary disks and their subsequent migration to the inner disk can ... | transport of co in protoplanetary disks: consequences of pebble formation, settling, and radial drift |
we present microlensing events in the 2015 korea microlensing telescope network (kmtnet) data and our procedure for identifying these events. in particular, candidates were detected with a novel “completed-event” microlensing event-finder algorithm. the algorithm works by making linear fits to a ({t}0,{t}{eff},{u}0) gr... | korea microlensing telescope network microlensing events from 2015: event-finding algorithm, vetting, and photometry |
many dynamical aspects of the solar system can be explained by the outer planets experiencing a period of orbital instability sometimes called the nice model. though often correlated with a perceived delayed spike in the lunar cratering record known as the late heavy bombardment (lhb), recent work suggests that this ev... | mars' growth stunted by an early giant planet instability |
carmenes is a spectrograph for radial velocity surveys of m dwarfs with the aim of detecting earth-mass planets orbiting in the habitable zones of their host stars. to ensure an optimal use of the carmenes guaranteed time observations, in this paper we investigate the correlation of activity and rotation for approximat... | carmenes input catalogue of m dwarfs. iii. rotation and activity from high-resolution spectroscopic observations |
most planets currently amenable to transit spectroscopy are close enough to their host stars to exhibit a relatively strong day to night temperature gradient. for hot planets this leads to a chemical composition dichotomy between the two hemispheres. in the extreme case of ultra-hot jupiters, some species, such as mole... | strong biases in retrieved atmospheric composition caused by day-night chemical heterogeneities |
recently, we introduced planetary atmospheric tool for observer noobs (platon), a python package that calculates model transmission spectra for exoplanets and retrieves atmospheric characteristics based on observed spectra. we now expand its capabilities to include the ability to compute secondary eclipse depths. we ha... | platon ii: new capabilities and a comprehensive retrieval on hd 189733b transit and eclipse data |
we present robust planet occurrence rates for kepler planet candidates around m stars for planet radii rp = 0.5-4 r⊕ and orbital periods p = 0.5-256 d using the approximate bayesian computation technique. this work incorporates the final kepler dr25 planet candidate catalogue and data products and augments them with up... | occurrence rates of planets orbiting m stars: applying abc to kepler dr25, gaia dr2, and 2mass data |
context. in recent decades, direct imaging has confirmed the existence of substellar companions (exoplanets or brown dwarfs) on wide orbits (>10 au) around their host stars. in striving to understand their formation and evolution mechanisms, in 2015 we initiated the sphere infrared survey for exoplanets (shine), a s... | the sphere infrared survey for exoplanets (shine). ii. observations, data reduction and analysis, detection performances, and initial results |
thermal convection is the dominant mechanism of energy transport in the outer envelope of the sun (one-third by radius). it drives global fluid circulations and magnetic fields observed on the solar surface. vigorous surface convection excites a broadband spectrum of acoustic waves that propagate within the interior an... | seismic sounding of convection in the sun |
high-resolution optical spectroscopy is a powerful tool to characterise exoplanetary atmospheres from the ground. the sodium d lines, with their large cross sections, are especially suited to studying the upper layers of atmospheres in this context. we report on the results from hot exoplanet atmosphere resolved with t... | hot exoplanet atmospheres resolved with transit spectroscopy (hearts). ii. a broadened sodium feature on the ultra-hot giant wasp-76b |
small organic molecules, such as c2h, hcn, and h2co, are tracers of the c, n, and o budget in protoplanetary disks. we present high-angular-resolution (10-50 au) observations of c2h, hcn, and h2co lines in five protoplanetary disks from the molecules with alma at planet-forming scales (maps) alma large program. we deri... | molecules with alma at planet-forming scales (maps). vi. distribution of the small organics hcn, c2h, and h2co |
a new class of exoplanets is beginning to emerge: planets with dayside atmospheres that resemble stellar atmospheres as most of their molecular constituents dissociate. the effects of the dissociation of these species will be varied and must be carefully accounted for. here we take the first steps toward understanding ... | increased heat transport in ultra-hot jupiter atmospheres through h2 dissociation and recombination |
sub-neptune-sized exoplanets represent the most common types of planets in the milky way, yet many of their properties are unknown. here, we present a prescription to adapt the capabilities of the stellar evolution toolkit modules for experiments in stellar astrophysics to model sub-neptune-mass planets with h/he envel... | evolutionary analysis of gaseous sub-neptune-mass planets with mesa |
magma oceans were once ubiquitous in the early solar system, setting up the initial conditions for different evolutionary paths of planetary bodies. in particular, the redox conditions of magma oceans may have profound influence on the redox state of subsequently formed mantles and the overlying atmospheres. the releva... | a magma ocean origin to divergent redox evolutions of rocky planetary bodies and early atmospheres |
meeting the increasing global demand for agricultural products without depleting the limited resources of the planet is a major challenge that humanity is facing. most studies on global food security do not make projections past the year 2050, just as climate change and increasing demand for food are expected to intens... | global food self-sufficiency in the 21st century under sustainable intensification of agriculture |
comets are thought to preserve almost pristine dust particles, thus providing a unique sample of the properties of the early solar nebula. the microscopic properties of this dust played a key part in particle aggregation during the formation of the solar system. cometary dust was previously considered to comprise irreg... | aggregate dust particles at comet 67p/churyumov-gerasimenko |
we provide a brief review of many aspects of the planetary physics of hot jupiters. our aim is to cover most of the major areas of current study while providing the reader with additional references for more detailed follow up. we first discuss giant planet formation and subsequent orbital evolution via disk driven tor... | hot jupiters: origins, structure, atmospheres |
context. dozens of protoplanetary disks have been imaged in scattered light during the last decade.aims: the variety of brightness, extension, and morphology from this census motivates a taxonomical study of protoplanetary disks in polarimetric light to constrain their evolution and establish the current framework of t... | evolution of protoplanetary disks from their taxonomy in scattered light: spirals, rings, cavities, and shadows |
the angular momentum deficit (amd) of a planetary system is a measure of its orbital excitation and a predictor of long-term stability. we adopt the amd-stability criterion to constrain the orbital architectures for exoplanetary systems. previously, he et al. showed through forward modeling (syssim) that the observed m... | architectures of exoplanetary systems. iii. eccentricity and mutual inclination distributions of amd-stable planetary systems |
exploiting the kepler transit data, we uncover a dramatic distinction in the prevalence of sub-jovian companions between systems that contain hot jupiters (hjs) (periods inward of 10 days) and those that host warm jupiters (wjs) (periods between 10 and 200 days). hjs, with the singular exception of wasp-47b, do not hav... | warm jupiters are less lonely than hot jupiters: close neighbors |
we present the discovery of a transiting hot jupiter orbiting hip 67522 (teff ∼ 5650 k; m* ∼ 1.2m⊙) in the 10-20 myr old sco-cen ob association. we identified the transits in the tess data using our custom notch filter planet search pipeline and characterize the system with additional photometry from spitzer; spectrosc... | tess hunt for young and maturing exoplanets (thyme). ii. a 17 myr old transiting hot jupiter in the sco-cen association |
the isotopic dichotomy between non-carbonaceous (nc) and carbonaceous (cc) meteorites indicates that meteorite parent bodies derive from two genetically distinct reservoirs, which presumably were located inside (nc) and outside (cc) the orbit of jupiter and remained isolated from each other for the first few million ye... | the non-carbonaceous-carbonaceous meteorite dichotomy |
meteorologists are forecasting a third consecutive year of la niña. some researchers say similar conditions could become more common as the planet warms. | rare `triple' la niña climate event looks likely — what does the future hold? |
we report the latest statistical analyses of superflares on solar-type (g-type main-sequence; effective temperature is 5100-6000 k) stars using all of the kepler primary mission data and gaia data release 2 catalog. we updated the flare detection method from our previous studies by using a high-pass filter to remove ro... | statistical properties of superflares on solar-type stars: results using all of the kepler primary mission data |
magmatism has occurred throughout earth's history. from the early earth to the modern plate-tectonic earth, the amount of magmatism has varied, but it has always occurred on multiple scales, in various tectonic environments and at various depths in the crust and mantle. magma compositions also vary. in this paper, we a... | passive magmatism on earth and earth-like planets |
reducing society's reliance on fossil fuels presents one of the most pressing energy and environmental challenges facing our planet. hydrogen, methane and carbon dioxide, which are some of the smallest and simplest molecules known, may lie at the centre of solving this problem through realization of a carbon-neutral en... | the role of metal-organic frameworks in a carbon-neutral energy cycle |
aircraft observations of meteorological, trace gas, and aerosol properties were made during may-september 2013 in the southeastern united states (us) under fair-weather, afternoon conditions with well-defined planetary boundary layer structure. optical extinction at 532 nm was directly measured at relative humidities (... | aerosol optical properties in the southeastern united states in summer - part 1: hygroscopic growth |
we provide a database of transit times and updated ephemerides for 382 planets based on data from the nasa transiting exoplanet survey satellite (tess) and previously reported transit times, which were scraped from the literature in a semiautomated fashion. in total, our database contains 8667 transit-timing measuremen... | tess transit timing of hundreds of hot jupiters |
context. exoplanet atmospheres are thought be built up from accretion of gas as well as pebbles and planetesimals in the midplanes of planet-forming disks. the chemical composition of this material is usually assumed to be unchanged during the disk lifetime. however, chemistry can alter the relative abundances of molec... | molecular abundances and c/o ratios in chemically evolving planet-forming disk midplanes |
we present 3d smoothed particle hydrodynamics simulations of protoplanetary discs undergoing a flyby by a stellar perturber on a parabolic orbit lying in a plane inclined relative to the disc mid-plane. we model the disc as a mixture of gas and dust, with grains ranging from 1 μm to 10 cm in size. exploring different o... | flybys in protoplanetary discs: i. gas and dust dynamics |
massive stars, which terminate their evolution in a cataclysmic explosion called a type-ii supernova, are the nuclear engines of galactic nucleosynthesis. among the elemental species known to be produced in these stars, the radioisotope 60fe stands out: this radioisotope has no natural, terrestrial production mechanism... | time-resolved 2-million-year-old supernova activity discovered in earth's microfossil record |
coherent low-frequency (≲200 mhz) radio emission from stars encodes the conditions of the outer corona, mass-ejection events and space weather1-5. previous low-frequency searches for radio-emitting stellar systems have lacked the sensitivity to detect the general population, instead largely focusing on targeted studies... | the population of m dwarfs observed at low radio frequencies |
exoplanet detection with precise radial velocity (rv) observations is currently limited by spurious rv signals introduced by stellar activity. we show that machine-learning techniques such as linear regression and neural networks can effectively remove the activity signals (due to starspots/faculae) from rv observation... | identifying exoplanets with deep learning. iv. removing stellar activity signals from radial velocity measurements using neural networks |
we present a comprehensive analysis of planetary phase variations, including possible planetary light offsets, using eighteen quarters of data from the kepler space telescope. our analysis found fourteen systems with significant detections in each of the phase curve components: planet’s phase function, secondary eclips... | changing phases of alien worlds: probing atmospheres of kepler planets with high-precision photometry |
the moniker rubble pile is typically applied to all solar system bodies >200 m and ≲10 km in diameter; in this size range, there is an abundance of evidence that nearly every object is bound primarily by self-gravity, with significant void space or bulk porosity between irregularly shaped constituent particles. the ... | rubble pile asteroids |
the planetary boundary layer height (pblh) is a very important parameter in the atmosphere, because it determines the range where the most effective dispersion processes take place, and serves as a constraint on the vertical transport of heat, moisture, and pollutants. as the only space-borne lidar, cloud-aerosol lidar... | an intercomparison of long-term planetary boundary layer heights retrieved from calipso, ground-based lidar, and radiosonde measurements over hong kong |
context. until recently, camera networks designed for monitoring fireballs worldwide were not fully automated, implying that in case of a meteorite fall, the recovery campaign was rarely immediate. this was an important limiting factor as the most fragile - hence precious - meteorites must be recovered rapidly to avoid... | fripon: a worldwide network to track incoming meteoroids |
we present an analysis of over 23,000 globally distributed wildfire smoke plume injection heights derived from multi-angle imaging spectroradiometer (misr) space-based, multi-angle stereo imaging. both pixel-weighted and aerosol optical depth (aod)-weighted results are given, stratified by region, biome, and month or s... | a global analysis of wildfire smoke injection heights derived from space-based multi-angle imaging |
giant kelp (macrocystis pyrifera) is the most widely distributed kelp species on the planet, constituting one of the richest and most productive ecosystems on earth, but detailed information on its distribution is entirely missing in some marine ecoregions, especially in the high latitudes of the southern hemisphere. h... | a high-resolution global map of giant kelp (macrocystis pyrifera) forests and intertidal green algae (ulvophyceae) with sentinel-2 imagery |
high-latitude environments store nearly half of the planet's below-ground organic carbon (oc), mostly in perennially frozen permafrost soils. climatic changes drive increased export of terrestrial oc into many aquatic networks, yet the role that circumpolar lakes play in mineralizing this carbon is unclear. here we dir... | negligible cycling of terrestrial carbon in many lakes of the arid circumpolar landscape |
the impact of the planetary boundary layer (pbl) structure on air pollution in northeast china, where frequently experiences air pollution episodes in autumn and winter, is not well understood due to a lack of observations. in this study, four pollution episodes during autumn and winter of 2016 at shenyang, a provincia... | impact of planetary boundary layer structure on the formation and evolution of air-pollution episodes in shenyang, northeast china |
this review examines recent theoretical developments in our understanding of turbulence in cold, non-magnetically active, planetesimal-forming regions of protoplanetary disks that we refer to throughout as “ohmic zones.” we give a brief background introduction to the subject of disk turbulence followed by a terse pedag... | the initial conditions for planet formation: turbulence driven by hydrodynamical instabilities in disks around young stars |
kelt-9 b, the hottest known exoplanet, with teq ~ 4400 k, is the archetype of a new planet class known as ultra-hot jupiters. these exoplanets are presumed to have an atmosphere dominated by neutral and ionized atomic species. in particular, hα and hβ balmer lines have been detected in the kelt-9 b upper atmosphere, su... | mass-loss rate and local thermodynamic state of the kelt-9 b thermosphere from the hydrogen balmer series |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.