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Preview of Comet C/2021 A1 (Leonard) and Its Encounter with Venus: Long period comet C/2021 A1 (Leonard) will approach Venus to within 0.029 au on 2021 December 18 and may subsequently graze the planet with its dust trail less than two days later. We observed C/2021 A1 with the Lowell Discovery Telescope on 2021 Januar...
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Detectability of Life Using Oxygen on Pelagic Planets and Water Worlds: The search for life on exoplanets is one of the grand scientific challenges of our time. The strategy to date has been to find (e.g., through transit surveys like Kepler) Earth-like exoplanets in their stars habitable zone, then use transmission sp...
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The Tidal-Thermal Evolution of the Pluto-Charon System: Existence of subsurface oceans on the satellites of the giant planets and Trans-Neptunian objects has been predicted for some time. Oceans on icy worlds exert a considerable influence on the dynamics of the ice-ocean system and, because of the astrobiological pote...
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The 1998 November 14 Occultation of GSC 0622-00345 by Saturn. I. Techniques for Ground-Based Stellar Occultations: On 1998 November 14, Saturn and its rings occulted the star GSC 0622-00345. We observed atmospheric immersion with NSFCAM at the National Aeronautics and Space Administration's Infrared Telescope Facilit...
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Short-term variability of comet C/2012 S1 (ISON) at 4.8 AU from the Sun: We observed comet C/2012 S1 (ISON) during six nights in February 2013 when it was at 4.8 AU from the sun. At this distance and time the comet was not very active and it was theoretically possible to detect photometric variations likely due to the ...
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ALMA Observations of Asymmetric Molecular Gas Emission from a Protoplanetary Disk in the Orion Nebula: We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of molecular line emission from d216-0939, one of the largest and most massive protoplanetary disks in the Orion Nebula Cluster (ONC). We m...
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HAT-P-58b -- HAT-P-64b: Seven Planets Transiting Bright Stars: We report the discovery and characterization of 7 transiting exoplanets from the HATNet survey. The planets, which are hot Jupiters and Saturns transiting bright sun-like stars, include: HAT-P-58b (with mass Mp = 0.37 MJ, radius Rp = 1.33 RJ, and orbital pe...
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A particle-based hybrid code for planet formation: We introduce a new particle-based hybrid code for planetary accretion. The code uses an $N$-body routine for interactions with planetary embryos while it can handle a large number of planetesimals using a super-particle approximation, in which a large number of small p...
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The Complex Rotational Light Curve of (385446) Manwë-Thorondor, a Multi-Component Eclipsing System in the Kuiper Belt: Kuiper Belt Object (385446) Manw\"e-Thorondor is a multi-object system with mutual events predicted to occur from 2014 to 2019. To detect the events, we observed the system at 4 epochs (UT 2016 Aug 2...
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An Ultra-Hot Neptune in the Neptune desert: About one out of 200 Sun-like stars has a planet with an orbital period shorter than one day: an ultra-short-period planet (Sanchis-ojeda et al. 2014; Winn et al. 2018). All of the previously known ultra-short-period planets are either hot Jupiters, with sizes above 10 Earth ...
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AcuA: the AKARI/IRC Mid-infrared Asteroid Survey: We present the results of an unbiased asteroid survey in the mid-infrared wavelength with the Infrared Camera (IRC) onboard the Japanese infrared satellite AKARI. About 20% of the point source events recorded in the AKARI All-Sky Survey observations are not used for the...
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The apparent tidal decay of WASP-4 b can be explained by the Rømer effect: Tidal orbital decay plays a vital role in the evolution of hot Jupiter systems. As of now, this was only observationally confirmed for the WASP-12 system. There are a few other candidates, including WASP-4 b, but no conclusive result could be ...
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Do we need to consider electron kinetic effects to properly model a planetary magnetosphere: the case of Mercury: The magnetosphere of Mercury is studied using an implicit full particle in cell simulation (PIC). We use a hybrid simulation where ions are full particles and electrons are considered as a fluid to start ...
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Dynamical evolution and end states of active and inactive Centaurs: We numerically study the dynamical evolution of observed samples of active and inactive Centaurs and clones that reach the Jupiter-Saturn region. Our aim is to compare the evolution between active and inactive Centaurs, their end states and their trans...
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Characterization of the KOI-94 System with Transit Timing Variation Analysis: Implication for the Planet-Planet Eclipse: The KOI-94 system is a closely-packed, multi-transiting planetary system discovered by the Kepler space telescope. It is known as the first system that exhibited a rare event called a "planet-plane...
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Toroidal vortices as a solution to the dust migration problem: In an earlier letter, we reported that dust settling in protoplanetary discs may lead to a dynamical dust-gas instability that produces global toroidal vortices. In this letter, we investigate the evolution of a dusty protoplanetary disc with two different ...
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Failure modes and conditions of a cohesive, spherical body due to YORP spin-up: This paper presents transition of the failure mode of a cohesive, spherical body due to YORP spin-up. On the assumption that the distribution of materials in the body is homogeneous, failed regions first appearing in the body at different...
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DART Mission Determination of Momentum Transfer: Model of Ejecta Plume Observations: The NASA Double Asteroid Redirection Test (DART) spacecraft will impact the secondary member of the [65803] Didymos binary in order to perform the first demonstration of asteroid deflection by kinetic impact. Determination of the mom...
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Evidence for a lost population of close-in exoplanets: We investigate the evaporation history of known transiting exoplanets in order to consider the origin of observed correlations between mass, surface gravity and orbital period. We show that the survival of the known planets at their current separations is consisten...
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The Effect of the Approach to Gas Disk Gravitational Instability on the Rapid Formation of Gas Giant Planets: Observational evidence suggests that gas disk instability may be responsible for the formation of at least some gas giant exoplanets, particularly massive or distant gas giants. With regard to close-in gas gi...
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Emergence of vortices at the edges of planet-driven gaps in protoplanetary discs: Young planets embedded in protoplanetary discs (PPDs) excite spiral density waves, which propagate, shock and deposit angular momentum in the disc. This results in gap opening around the planetary orbit, even for low (sub-thermal) mass ...
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Heating of the Atmospheres of Short-orbit Exoplanets by Their Rapid Orbital Motion Through an Extreme Space Environment: Exoplanets with short orbit period reside very close to their host stars. They transition very rapidly between different sectors of the circumstellar space environment along their orbit, leading to...
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Binary Survival in the Outer Solar System: As indicated by their special characteristics, the cold classical Kuiper belt objects (KBOs) formed and survived at 42-47 au. Notably, they show a large fraction of equal-size binaries whose formation is probably related to the accretion of KBOs themselves. These binaries are ...
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The Hubble Wide Field Camera 3 Test of Surfaces in the Outer Solar System: The Compositional Classes of the Kuiper Belt: We present the first results of the Hubble Wide Field Camera 3 Test of Surfaces in the Outer Solar System (H/WTSOSS). The purpose of this survey was to measure the surface properties of a large num...
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Searching for Saturn's Dust Swarm: Limits on the size distribution of Irregular Satellites from km to micron sizes: We describe a search for dust created in collisions between the Saturnian irregular satellites using archival \emph{Spitzer} MIPS observations. Although we detected a degree scale Saturn-centric excess ...
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KMT-2021-BLG-0912Lb: A microlensing super Earth around a K-type star: The light curve of the microlensing event KMT-2021-BLG-0912 exhibits a very short anomaly relative to a single-lens single-source form. We investigate the light curve for the purpose of identifying the origin of the anomaly. We model the light curve ...
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Terrestrial planet formation in low-mass disks: dependence with initial conditions: In general, most of the studies of terrestrial-type planet formation typically use ad hoc initial conditions. In this work we improved the initial conditions described in Ronco & de El\'ia (2014) starting with a semi-analytical model ...
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The PLATO 2.0 Mission: PLATO 2.0 has recently been selected for ESA's M3 launch opportunity (2022/24). Providing accurate key planet parameters (radius, mass, density and age) in statistical numbers, it addresses fundamental questions such as: How do planetary systems form and evolve? Are there other systems with plane...
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Asteroid Models from Multiple Data Sources: In the past decade, hundreds of asteroid shape models have been derived using the lightcurve inversion method. At the same time, a new framework of 3-D shape modeling based on the combined analysis of widely different data sources such as optical lightcurves, disk-resolved im...
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K2-288Bb: A Small Temperate Planet in a Low-mass Binary System Discovered by Citizen Scientists: Observations from the Kepler and K2 missions have provided the astronomical community with unprecedented amounts of data to search for transiting exoplanets and other astrophysical phenomena. Here, we present K2-288, a lo...
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Initial mass function of planetesimals formed by the streaming instability: The streaming instability is a mechanism to concentrate solid particles into overdense filaments that undergo gravitational collapse and form planetesimals. However, it remains unclear how the initial mass function of these planetesimals depe...
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RVSPY -- Radial Velocity Survey for Planets around Young Stars. Target characterization and high-cadence survey: We introduce our Radial Velocity Survey for Planets around Young stars (RVSPY), characterise our target stars, and search for substellar companions at orbital separations smaller than a few au from the hos...
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Global simulations of protoplanetary disks with net magnetic flux: I. Non-ideal MHD case: The planet-forming region of protoplanetary disks is cold, dense, and therefore weakly ionized. For this reason, magnetohydrodynamic (MHD) turbulence is thought to be mostly absent, and another mechanism has to be found to expla...
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Breaking the Ice: Planetesimal Formation at the Snowline: Recently Saito & Sirono (2011) proposed that large ice aggregates which drift in- wards in protoplanetary disks break up during sublimation, ejecting embedded silicate particles. This would lead to a concentration of small solid particles close to the snow- line...
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FU Orionis outbursts, preferential recondensation of water ice, and the formation of giant planets: Ices, including water ice, prefer to recondense onto pre-existing nuclei rather than spontaneously forming grains from a cloud of vapor. Interestingly, different potential recondensation nuclei have very different prop...
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Revisiting parameters for the WASP-1 planetary system: We present thirteen new transit light curves for the WASP-1 b exoplanet. Observations were acquired with 0.5 - 1.2-m telescopes between 2007 and 2013. Our homogeneous analysis, which also includes the literature data, results in determining precise system parameter...
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Mapping out the parameter space for photoevaporation and core-powered mass-loss: Understanding atmospheric escape in close-in exoplanets is critical to interpreting their evolution. We map out the parameter space over which photoevaporation and core-powered mass loss dominate atmospheric escape. Generally, the transi...
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Comparison of space weathering spectral changes induced by solar wind and micrometeoroid impacts using ion- and femtosecond-laser-irradiated olivine and pyroxene: Space weathering is a process that changes the surface of airless planetary bodies. Prime space weathering agents are solar wind irradiation and micromet...
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An Orbitrap-based laser desorption/ablation mass spectrometer designed for spaceflight: RATIONALE: The investigation of cryogenic planetary environments as potential harbors for extant life and/or contemporary sites of organic synthesis represents an emerging focal point in planetary exploration. Next generation inst...
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A Sawtooth-like Timeline for the First Billion Year of Lunar Bombardment: We revisit the early evolution of the Moon's bombardment. Our work combines modeling (based on plausible projectile sources and their dynamical decay rates) with constraints from the lunar crater record, radiometric ages of the youngest lunar bas...
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Revisiting $ε$ Eridani with NEID: Identifying New Activity-Sensitive Lines in a Young K Dwarf Star: Recent improvements in the sensitivity and precision of the radial velocity (RV) method for exoplanets have brought it close, but not quite to, the threshold ($\sim$10 cm/s) required to detect Earth-mass and other pote...
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Collateral Effects on Solar Nebula Oxygen Isotopes due to Injection of 26Al by a Nearby Supernova: Injection of material from a core-collapse supernova into the solar system's already-formed disk is one proposed mechanism for producing the short-lived radionuclides, such as 26Al and 41Ca, inferred from isotopic studi...
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The Chicxulub Impactor: Comet or Asteroid?: A recent paper by Siraj & Loeb (2021) entitled "Breakup of a long-period comet as the origin of the dinosaur extinction" attempts to revive the perennial debate about what type of body hit the Earth 66 million years ago, triggering the end-Cretaceous extinction. Here we criti...
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Growth of Jupiter: Formation in Disks of Gas and Solids and Evolution to the Present Epoch: [Abridged] The formation of Jupiter is modeled via core-nucleated accretion, and the planet's evolution is simulated up to the present epoch. The growth from a small embryo until gas accretion overtakes solids' accretion was p...
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Globally disruptive events show predictable timing patterns: Globally disruptive events include asteroid/comet impacts, large igneous provinces and glaciations, all of which have been considered as contributors to mass extinctions. Understanding the overall relationship between the timings of the largest extinctions an...
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Information in the Reflected Light Spectra of Widely Separated Giant Exoplanets: Giant exoplanets located >1 AU away from their parent stars have atmospheric environments cold enough for water and/or ammonia clouds. We have developed a new equilibrium cloud and reflected light spectrum model, ExoREL, for widely separ...
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Large grains can grow in circumstellar discs: We perform coagulation & fragmentation simulations to understand grain growth in T Tauri & brown dwarf discs. We present a physically-motivated approach using a probability distribution function for the collision velocities and separating the deterministic & stochastic velo...
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Observation of metre-scale impactors by the Desert Fireball Network: The Earth is impacted by 35-40 metre-scale objects every year. These meteoroids are the low mass end of impactors that can do damage on the ground. Despite this they are very poorly surveyed and characterised, too infrequent for ground based fireball ...
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Rotation acceleration of asteroids (10115) 1992 SK, (1685) Toro, and (1620) Geographos due to the YORP effect: The rotation state of small asteroids is affected by the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect, which is a net torque caused by solar radiation directly reflected and thermally reemitted from t...
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Setting the stage for the search for life with the Habitable Worlds Observatory: Properties of 164 promising planet survey targets: The Decadal Survey on Astronomy and Astrophysics 2020 (Astro2020) has recommended that NASA realize a large IR/O/UV space telescope optimized for high-contrast imaging and spectroscopy o...
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First detection of gas-phase methanol in a protoplanetary disk: The first detection of gas-phase methanol in a protoplanetary disk (TW Hya) is presented. In addition to being one of the largest molecules detected in disks to date, methanol is also the first disk organic molecule with an unambiguous ice chemistry origin...
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Direct Imaging of Exoplanets at the Era of the Extremely Large Telescopes: Within ten years, the era of large-scale systematics surveys will decay thanks to a complete census of exoplanetary systems within 200 pc from the Sun. With the first Lights foreseen between 2024 and 2028, the new generation of extremely large...
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Sulfuric acid as a cryofluid and oxygen isotope reservoir of planetesimals: The Sun exhibits a depletion in $^{17,18}$O relative to $^{16}$O by 6 % compared to the Earth and Moon$^{1}$. The origin of such a non-mass-dependent isotope fractionation has been extensively debated since the three-isotope-analysis$^{2}$ be...
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The Migration of Gap-Opening Planets is not Locked to Viscous Disk Evolution: Most standard descriptions of Type II migration state that massive, gap-opening planets must migrate at the viscous drift rate. This is based on the idea that the disk is separated into an inner and outer region and gas is considered unable...
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Stellar wind-magnetosphere interaction at exoplanets: computations of auroral radio powers: We present calculations of the auroral radio powers expected from exoplanets with magnetospheres driven by an Earth-like magnetospheric interaction with the solar wind. Specifically, we compute the twin cell-vortical ionospher...
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Line Ratios Reveal N2H+ Emission Originates Above the Midplane in TW Hydrae: Line ratios for different transitions of the same molecule have long been used as a probe of gas temperature. Here we use ALMA observations of the N2H+ J~=~1-0 and J~=~4-3 lines in the protoplanetary disk around TW Hya to derive the temperat...
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Imaging diagnostics for transitional discs: Transitional discs are a special type of protoplanetary discs where planet formation is thought to be taking place. These objects feature characteristic inner cavities and/or gaps of a few tens of AUs in the sub-millimitre images of the disc. This signature suggests a localis...
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A new pattern in Saturn's D ring created in late 2011: Images obtained by the Cassini spacecraft between 2012 and 2015 reveal a periodic brightness variation in a region of Saturn's D ring that previously appeared to be rather featureless. Furthermore, the intensity and radial wavenumber of this pattern have decreased ...
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An optimised survey strategy for the ERIS/NIX imager: searching for young giant exoplanets and very low mass brown dwarfs using the K-peak custom photometric filter: We present optimal survey strategies for the upcoming NIX imager, part of the ERIS instrument to be installed on the Very Large Telescope (VLT). We wi...
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Eleven Multi-planet Systems from K2 Campaigns 1 & 2 and the Masses of Two Hot Super-Earths: We present a catalog of 11 multi-planet systems from Campaigns 1 and 2 of the K2 mission. We report the sizes and orbits of 26 planets split between seven 2-planet systems and four 3-planet systems. These planets stem from a s...
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Photometry of 10 Million Stars from the First Two Years of TESS Full Frame Images: The Transiting Exoplanet Survey Satellite (TESS) is the first high-precision full-sky photometry survey in space. We present light curves from a magnitude limited set of stars and other stationary luminous objects from the TESS Full Fr...
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Outwards migration for planets in stellar irradiated 3D discs: For the very first time we present 3D simulations of planets embedded in stellar irradiated discs. It is well known that thermal effects could reverse the direction of planetary migration from inwards to outwards, potentially saving planets in the inner, op...
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Mineral dust increases the habitability of terrestrial planets but confounds biomarker detection: Identification of habitable planets beyond our solar system is a key goal of current and future space missions. Yet habitability depends not only on the stellar irradiance, but equally on constituent parts of the planeta...
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Stellar Winds and Dust Avalanches in the AU Mic Debris Disk: We explain the fast-moving, ripple-like features in the edge-on debris disk orbiting the young M dwarf AU Mic. The bright features are clouds of sub-micron dust repelled by the host star's wind. The clouds are produced by avalanches: radial outflows of dust t...
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Thermal and orbital evolution of low-mass exoplanets: Thermal, orbital, and rotational dynamics of tidally loaded exoplanets are interconnected by intricate feedback. The rheological structure of the planet determines its susceptibility to tidal deformation and, as a consequence, participates in shaping its orbit. The ...
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The Effect of Multiple Heat Sources on Exomoon Habitable Zones: With dozens of Jovian and super-Jovian exoplanets known to orbit their host stars in or near the stellar habitable zones, it has recently been suggested that moons the size of Mars could offer abundant surface habitats beyond the solar system. Several sear...
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Stellar orbit evolution in close circumstellar disc encounters: The formation and early evolution of circumstellar discs often occurs within dense, newborn stellar clusters. For the first time, we apply the moving-mesh code AREPO, to circumstellar discs in 3-D, focusing on disc-disc interactions that result from stella...
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True Polar Wander on Dynamic Planets: Approximative Methods vs. Full Solution: Almost three decades ago, the problem of long term polar wander on a dynamic planet was formulated and simplified within the framework of normal mode theory. The underlying simplifications have been debated ever since, recently in a series...
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The Rossiter-McLaughlin effect and exoplanet transits: A delicate association at medium and low spectral resolution: The characterization of exoplanetary atmospheres via transit spectroscopy is based on the comparison between the stellar spectrum filtered through the atmosphere and the unadulterated spectrum from the...
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From exo-Earths to exo-Venuses -- Flux and Polarization Signatures of Reflected Light: Terrestrial exoplanets in habitable zones are ubiquitous. It is, however, unknown which have Earth-like or Venus-like climates. Distinguishing different planet-types is crucial for determining whether a planet could be habitable. W...
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HELIOS: An Open-source, GPU-accelerated Radiative Transfer Code For Self-consistent Exoplanetary Atmospheres: We present the open-source radiative transfer code named HELIOS, which is constructed for studying exoplanetary atmospheres. In its initial version, the model atmospheres of HELIOS are one-dimensional and pla...
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Photodissociation and induced chemical asymmetries on ultra-hot gas giants. A case study of HCN on WASP-76 b: Recent observations have resulted in the detection of chemical gradients on ultra-hot gas giants. Notwithstanding their high temperature, chemical reactions in ultra-hot atmospheres may occur in disequilibriu...
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The Beam Balance -- Measuring Binary Systems via Relativistic Beaming Signals from Stars and their Companions: In this paper I show that the concept of relativistic beaming -- the process by which light emitted by a fast moving sources is lensed towards the direction of motion -- can be easily extended to model the s...
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The Role of Early Giant Planet Instability in the Terrestrial Planet Formation: The terrestrial planets are believed to have formed by violent collisions of tens of lunar- to Mars-size protoplanets at time t<200 Myr after the protoplanetary gas disk dispersal (t_0). The solar system giant planets rapidly formed durin...
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Oscillations in the Habitable Zone around Alpha Centauri B: The Alpha Centauri AB system is an attractive one for radial velocity observations to detect potential exoplanets. The high metallicity of both Alpha Centauri A and B suggest that they could have possessed circumstellar discs capable of forming planets. As the...
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Identification of asteroids using the Virtual Observatory: the WFCAM Transit Survey: The nature and physical properties of asteroids, in particular those orbiting in the near-Earth space, are of scientific interest and practical importance. Exoplanet surveys can be excellent resources to detect asteroids, both alread...
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Mercury's geochronology revised by applying Model Production Functions to Mariner 10 data: geological implications: Model Production Function chronology uses dynamic models of the Main Belt Asteroids (MBAs) and Near Earth Objects (NEOs) to derive the impactor flux to a target body. This is converted into the crater s...
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The Carbon-Deficient Evolution of TRAPPIST-1c: Transiting planets orbiting M dwarfs provide the best opportunity to study the atmospheres of rocky planets with current facilities. As JWST enters its second year of science operations, an important initial endeavor is to determine whether these rocky planets have atmosph...
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On the Outer Edges of Protoplanetary Dust Disks: The expectation that aerodynamic drag will force the solids in a gas-rich protoplanetary disk to spiral in toward the host star on short timescales is one of the fundamental problems in planet formation theory. The nominal efficiency of this radial drift process is in co...
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TESS Photometric Mapping of a Terrestrial Planet in the Habitable Zone: Detection of Clouds, Oceans, and Continents: To date, a handful of exoplanets have been photometrically mapped using phase-modulated reflection or emission from their surfaces, but the small amplitudes of such signals have limited previous maps a...
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Is the hot, dense sub-Neptune TOI-824b an exposed Neptune mantle? Spitzer detection of the hot day side and reanalysis of the interior composition: The Kepler and TESS missions revealed a remarkable abundance of sub-Neptune exoplanets. Despite this abundance, our understanding of the nature and compositional divers...
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Transformation of Trojans into Quasi-Satellites During Planetary Migration and Their Subsequent Close-Encounters with the Host Planet: We use numerical integrations to investigate the dynamical evolution of resonant Trojan and quasi-satellite companions during the late stages of migration of the giant planets Jupiter...
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Explosion of Comet 17P/Holmes as revealed by the Spitzer Space Telescope: An explosion on comet 17P/Holmes occurred on 2007 Oct 23, projecting particulate debris of a wide range of sizes into the interplanetary medium. We observed the comet using the Spitzer spectrograph on 2007 Nov 10 and 2008 Feb 27, and the photomet...
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Collisions of small ice particles under microgravity conditions (II): Does the chemical composition of the ice change the collisional properties?: Context: Understanding the collisional properties of ice is important for understanding both the early stages of planet formation and the evolution of planetary ring syste...
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Long lived dust rings around HD169142: Recent ALMA observations of the protoplanetary disc around HD~169142 reveal a peculiar structure made of concentric dusty rings: a main ring at $\sim$20 au, a triple system of rings at $\sim 55-75$ au in millimetric continuum emission and a perturbed gas surface density from the $...
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Aggregate dust particles at comet 67P/Churyumov-Gerasimenko: 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 Syst...
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Revisiting the distributions of Jupiter's irregular moons: II. orbital characteristics: This paper statistically describes the orbital distribution laws of Jupiter's irregular moons, most of which are members of the Ananke, Carme and Pasiphae groups. By comparing 19 known continuous distributions, it is verified that...
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Dynamical Evolution of the Earth-Moon Progenitors - Whence Theia?: We present integrations of a model Solar System with five terrestrial planets (beginning ~30-50 Myr after the formation of primitive Solar System bodies) in order to determine the preferred regions of parameter space leading to a giant impact that resul...
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WASP-131 b with ESPRESSO I: A bloated sub-Saturn on a polar orbit around a differentially rotating solar-type star: In this paper, we present observations of two high-resolution transit datasets obtained with ESPRESSO of the bloated sub-Saturn planet WASP-131~b. We have simultaneous photometric observations with NGTS...
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Physical Characterisation of Interstellar Comet 2I/2019 Q4 (Borisov): We present a study of interstellar comet 2I/2019 Q4 (Borisov) using both preperihelion and postperihelion observations spanning late September 2019 through late January 2020. The intrinsic brightness of the comet was observed to continuously decline ...
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CCD polarimetry of distant comets C/2010 S1 (LINEAR) and C/2010 R1 (LINEAR) at the 6-m telescope of the SAO RAS: We present first measurements of the degree of linear polarization of distant comets C/2010 S1 (LINEAR) and C/2010 R1 (LINEAR) at heliocentric distances r= 5.9 - 7.0 AU. Observations were carried out with ...
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The impact of faculae on the radius determination of exoplanets: The case of the M-star GJ1214: Precise measurements of exoplanets radii are of key importance for our understanding of the origin and nature of these objects. Measurement of the planet radii using the transit method have reached a precision that the eff...
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Disentangling Atmospheric Compositions of K2-18 b with Next Generation Facilities: Recent analysis of the planet K2-18b has shown the presence of water vapour in its atmosphere. While the H2O detection is significant, the Hubble Space Telescope (HST) WFC3 spectrum suggests three possible solutions of very different n...
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The HARPS search for southern extrasolar planets. XXIII. 8 planetary companions to low-activity solar-type stars: In this paper, we present our HARPS radial-velocity data for eight low-activity solar-type stars belonging to the HARPS volume-limited sample: HD6718, HD8535, HD28254, HD290327, HD43197, HD44219, HD148156...
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Effect of Finite Larmor Radius on the Cosmic Ray Penetration into an Interplanetary Magnetic Flux Rope: We discuss a mechanism for cosmic ray penetration into an interplanetary magnetic flux rope, particularly the effect of the finite Larmor radius and magnetic field irregularities. First, we derive analytical soluti...
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Rotation periods of late-type dwarf stars from time-series high-resolution spectroscopy of chromospheric indicators: We determine rotation periods of a sample of 48 late F-type to mid-M dwarf stars using time-series high-resolution spectroscopy of the Ca II H&K and H-alpha chromospheric activity indicators. We find g...
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Is Extraterrestrial Life Suppressed on Subsurface Ocean Worlds due to the Paucity of Bioessential Elements?: The availability of bioessential elements for "life as we know it", such as phosphorus (P) or possibly molybdenum (Mo), is expected to restrict the biological productivity of extraterrestrial biospheres. Here,...
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The Next Generation Transit Survey (NGTS): We describe the Next Generation Transit Survey (NGTS), which is a ground-based project searching for transiting exoplanets orbiting bright stars. NGTS builds on the legacy of previous surveys, most notably WASP, and is designed to achieve higher photometric precision and hence...
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Potential Backup Targets for Comet Interceptor: Comet Interceptor is an ESA F-class mission expected to launch in 2028 on the same launcher as ESA's ARIEL mission. Comet Interceptor's science payload consists of three spacecraft, a primary spacecraft that will carry two smaller probes to be released at the target. The ...
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An Analytic Method to determine Habitable Zones for S-Type Planetary Orbits in Binary Star Systems: With more and more extrasolar planets discovered in and around binary star systems, questions concerning the determination of the classical Habitable Zone arise. Do the radiative and gravitational perturbations of the ...
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