New papers on Planets & exoplanets
78 new papers on planets & exoplanets in the last 7 days, within Space & cosmos. These are the 50 Pipette rates most worth reading, with the main result in the authors' own words.
The best of the week
Upside down: GJ3090 b the first retrograde exoplanet around an M dwarf detected with NIRPS
Our results establish GJ3090 b as the first planet on a retrograde orbit discovered around an M dwarf and the first highly misaligned confirmed multi-planet system without a known massive companion.
Preprint with a published versionClaims a big stepEnceladus-like geochemistry fuels methanogenesis under extreme CO 2 limitation
Here, we show that simulated Enceladus’ ocean chemistry containing high concentrations of dissolved inorganic carbon and H 2 from mineral-water reactions enables growth of the chemolithoautotroph H 2 -oxidizing methanogen Methanothermococcus okinawensis until pH 11, far exceeding its previously known pH limit.
Peer-reviewed journalMultiband Color Monitoring of 3I/ATLAS through Ground-Based Relay Observations
These observations provide the first densely sampled, apparition-long characterization of the broadband optical colors of an interstellar comet and establish a benchmark for comparison with future interstellar objects.
PreprintClaims a big stepAn Open Cluster Origin for Most Solar-Type Binaries in the Solar Neighborhood and Implications for Primordial Planet Stability
We find that at least ~53% of solar-type field binaries formed in OCs with initial masses > 200 M_Sun, where dynamical processing becomes significant.
PreprintInside the Eirenesphere: The Interplay of Porosity, Heat Flux and Mineralogy in Exoplanetary Aquable and Habitable Layers
Here, we present a geophysical model integrating internal radial structure, mineralogy, radiogenic heat, and pressure-dependent porosity to quantify the three-dimensional habitable volume-the eirenesphere-of rocky exoplanets.
PreprintBold claims, read criticallyCassini CDA observes compositional segregation of Enceladus’ ice grains from slow freezing and fragmentation of oceanic spray
Here, we present an analysis on the basis of ≈1000 mass spectra of individual Type 3 E ring ice grains recorded by Cassini’s Cosmic Dust Analyzer (CDA), revealing a large compositional diversity among these grains.
Peer-reviewed journalTectonics on early Earth driven by Earth's changing shape during tidal recession of the Moon
Further, the subsequent changes in Earth's shape in response to its slowing rotation rate could have driven extensive tectonic activity and modulated the response of the crust to other forces.
PreprintSearching for Embedded Protoplanets with the Keck/NIRC2 Vortex Coronagraph: Confirmation of a Core-accretion Planet in the Narrow Gap of the Elias 2-24 Disk
We confirm the planetary candidate around Elias 2-24, previously proposed in the literature, at a separation of 39431 mas (54.9.3 au) and a position angle of 298.83.2, within the narrow gap of the protoplanetary disk.
Preprint with a published versionHigh-resolution optical spectroscopy reveals the distinctive volatile composition of the interstellar comet 3I/ATLAS
3I/ATLAS therefore extends the known diversity of cometary compositions, demonstrating that volatile reservoirs in other planetary systems can differ substantially from those sampled by Solar System comets.
PreprintA fifth companion in the HR 8799 system revealed by Gaia
Here we combine Gaia absolute astrometry and Hipparcos-Gaia proper-motion anomalies with radial velocities and high-contrast imaging to reveal an additional close-in substellar companion.
PreprintKelvin-Helmholtz vortices in the Martian +E hemisphere downstream of crustal magnetic anomalies
Here we report the observation of a coherent train of fully developed KH vortices in the traditionally unfavorable +E hemisphere of Mars, using in-situ MAVEN measurements.
PreprintRecovering the Morning and Evening Limbs of WASP-94Ab from Its Limb-Averaged JWST Transmission Spectrum
This work demonstrates that compositional information survives limb averaging for WASP-94Ab, suggesting that 2-TP retrievals can be used to identify limb-asymmetry and extend metallicity studies beyond the small set of planets amenable to limb-resolved spectroscopy.
PreprintA Hadean timeline for the emergence of the RNA World
Here, we conclude that a proposed early stage of life - the RNA World - appeared at ca. 4.33 Ga by tracking the near-surface thermal stability of key biomolecules comprising postulated RNA organisms.
Peer-reviewed journalBold claims, read criticallyJWST MEP - A World Under Spotty Starlight: Detection of CO2 and H2O in the Hot Saturn WASP-52b with JWST NIRSpec G395H
Our spectrum reveals the first detection of CO2 in WASP-52b's atmosphere (ln B = 54 / >10), with a retrieved abundance of log CO2 = -5.09 (+1.09/-1.14), and confirmation of H2O (ln B = 5.9 / 3-4), with an abundance of log H2O = -3.41 (+1.04/-1.04).
Preprint with a published versionSuper-Earth Interiors Shrink by About 10% as They Crystallise
In volatile-poor super-Earths of 1 to 10 Earth masses, the silicate interior contracts by about 10 % of its molten radius through cooling and crystallisation, nearly independent of planet mass and driven by the thinning silicate shell alone.
PreprintTime-resolved JWST Retrieval Analysis of the Coldest Brown Dwarf: Temperature and Chemical Variations in WISE 0855-07
From the time-series retrievals, we find that the primary source of the observed spectral variability is driven by the variations in the thermal structure, which range from ~1 to <100 K from epoch to epoch, particularly between the pressures of ~0.4 and 10 bar.
Preprint with a published versionDeep HST/STIS Coronagraphic Imaging of the Pictoris Debris Disk: On the Scattered Light Component of the Cat's Tail
We report the detection of the visible/near-infrared scattered light component of the Cat's Tail substructure.
PreprintMolecular mapping of an exoplanet with JWST: NH3 detection in the temperate super-Jupiter Epsilon Indi Ab
Using molecular mapping, we securely identify the presence of NH3 (maximum S/N = 15.6), H2O (maximum S/N = 10.8), CH4 (S/N = 3.8) and marginally detect CO2 (S/N = 2.5).
PreprintAsteroids Impacting the Solar System Planets and the Moon. I. Collision Rates from N-body Simulations
We predict over 300 years there will be impactors on Venus (all NEOs), on Earth (NEOs and JFCs), on Jupiter (mainly MBAs and JFCs), on Saturn (mainly Centaurs), and none on the remaining planets with the upper limits spanning (inner planets) to (outer planets; weak constraint).
PreprintMagmatic origin of the Dewar magnetic anomaly: Implications for an early lunar dynamo
These findings link a magnetic anomaly to its geologic origin and magnetizing field, providing constraints on the lunar magnetic and volcanic history.
Peer-reviewed journalJWST and HST Confirm Transit Timing Variations for the Ultra-Hot Jupiter TOI-2109 b
We find very strong evidence for sinusoidal TTVs over a linear ephemeris (BIC of 33.6), consistent with a nearby planetary companion as suggested by J.-V.
PreprintA Very Fast Symplectic Integrator for Planetary Systems: WHFast512 in x86 Assembly
In this paper, we describe significant speed and accuracy improvements to the WHFast512 integrator.
PreprintBold claims, read criticallyCode availableRotational Mapping and Regional Atmospheric Retrievals of Variable Brown Dwarfs: Application to Luhman 16B and SIMP 0136
We present a Bayesian framework for converting time-resolved spectroscopy into rotation-inferred regional spectra and atmospheric constraints for variable brown dwarfs.
PreprintRevealing the Shiny Nature of Lava Worlds: Small Planet Phase Curves with TESS
We use these results and previous results from Kepler and CHEOPS to homogeneously derive geometric albedos for these planets, revealing that lava worlds generally show high albedos compared to the low geometric albedos measured for hot Jupiters at similar temperatures.
PreprintSouth Pole-Aitken basin sample Return and eXploration (SPARX) Science Definition Team Report
Convened by NASA in response to OWL Decadal Survey recommendations, the SPARX report provides analysis on prioritized science objectives, measurement requirements, implementation architectures, and a design reference mission for a South Pole-Aitken basin sample return mission.
PreprintBold claims, read criticallyMeteoritic organic matter records primitive oxygen reservoirs of the solar system
Remarkably, the IOM from primitive Type 1 and 2 CCs-including CI, CM, CR, Bells, and Tarda-have oxygen isotope compositions that cluster on or near the CCAM line, which is itself related to the mixing of primitive oxygen isotope reservoirs residing within the early SS.
Peer-reviewed journalNucleosynthetic constraints on the origin of Bennu and CI-like asteroids
These results demonstrate that CI-like bodies accreted from a common dust reservoir with affinities to both inner (noncarbonaceous) and outer (carbonaceous) Solar System materials.
Peer-reviewed journalBold claims, read criticallyProbing Exoplanetary Rings with Asterodensity Profiling: A PhotoRing Analysis of Kepler-51
While the required impact parameters and stellar densities show tension with independent constraints -attributable to Kepler's 30-minute cadence- this study presents the first complete application of the PR effect, offered as a methodological demonstration and exclusion experiment rather than as evidence that rings are present.
PreprintAsteroids Impacting the Solar System Planets and the Moon. III. Real Impacts from Known Objects and LSST Discovery Predictions
These results demonstrate that LSST can identify a subset of planetary impactors years to centuries before collision, providing a new observational pathway for testing source-population models and the impact-rate mismatch.
PreprintA Collisional Origin for Ice-rich Iapetus and Titan's Anomalous Eccentricity
These results establish the collisional production of an icy debris reservoir, with some material on orbits of large semimajor axis; raising Iapetus's periapse would require gas drag or dynamical friction.
PreprintRosetta Earth Flyby Anomaly Revisited: Assessing Physical Contributions through Orbital Dynamics Analysis
Outlook: During investigations of Earth's albedo effect, a possible explanation for an artificial velocity increase was identified.
Preprint with a published versionEuropa smooth plains formation: a SPH cryovolcanic model
Our simulations show that snow is a relevant physical analogue for cryolava, as the resulting flows closely match the smooth plains observed by Galileo in both extent and morphology.
PreprintLaboratory Evidence that Methanol-Rich Ice Mantles Lower Methyl Formate Binding Energies
We find that MF binds more weakly to CHOH ice than to HO-rich substrates, with representative binding energies of ~6247K for amorphous HO, ~6213K for crystalline HO, and ~5469K for amorphous CHOH.
PreprintPost-perihelion Photometric and Spectroscopic Monitoring of the Interstellar Comet 3I/ATLAS
The production rates and rate ratios indicate that the composition of the 3I/ATLAS transitioned from carbon-depleted (pre-perihelion) to carbon-typical (post-perihelion).
PreprintM Dwarf Singles and Multis Have Dissimilar Metallicities Indicating Different Origins
We use a homogeneous sample of FGK and M dwarf chemical abundances to demonstrate that M dwarf multis are significantly more metal-poor than singles ( = 0.00079), even when we only consider small (<4 ) planets ( = 0.0013).
PreprintComparative analysis of Neural Networks approaches for Initial Orbit Determination of Near-Earth Objects
Each model returns an estimate on every arc by construction, so we assess instead whether that estimate is dynamically admissible: on a held-out test set of arcs the physics-informed model places of its predictions inside the admissible region, against for the data-driven baseline, whereas Gauss's and Laplace's methods return a solution on only and of the same arcs and collapse onto the degenerate root in about nine of those cases out of ten.
PreprintSimulating the thermodynamics of gas, radiation, and multispecies dust: Method and applications to protoplanetary disks
With this motivation, we have devised a radiation-hydrodynamics scheme for the PLUTO code with energy exchange (via absorption, emission, and collisions) for gas, radiation, and multiple species of dust.
PreprintTransport and Thermochemical Kinetics of Alkali Species in Hot Jupiter Atmospheres: Implications for Magnetic Models
In this work, we investigate the thermochemical kinetics of alkali species within a hot Jupiter atmosphere, thus allowing for the thermal ionisation fraction to depart from equilibrium, and demonstrate that quenching of ions occurs between 1 and 10 mbar.
PreprintThe Science Potential of Characterizing Gas Giant Exoplanets with HWO
We find that HWO should be able to achieve S/N 5 broadband visible-light detections of gas giants in this instellation range within 5 minutes of integration.
PreprintJust a Phase? Weakening Vertical Shear Instability Explains Class II Disk Morphologies: Simulations with dust coagulation, sedimentation, thermal relaxation, and backreaction
We present simulations of protoplanetary disks with VSI that are consistent with the observed thin-disk geometries, while maintaining the commonly observed bowl-shaped morphology in scattered light images at micrometer wavelength.
PreprintBold claims, read criticallyOn the Long-Term Orbital Behaviour of Hilda Asteroids - I. Global Stability Patterns and Catalogue
We present the results of detailed dynamical integrations of 2,699 numbered asteroids in the Hilda region, following 243 clones of each Hilda for 1 Gyr under the influence of the giant planets and the Sun; 54.7% of our sample exhibit extreme dynamical stability, with all clones of 1,475 Hildas remaining trapped in the 3:2 MMR for the full 1 Gyr of our integrations.
PreprintA Possible Complication of Using the 4.14 {\mu}m band to Assess D/H Ratios on Icy Bodies
While we suspect that existing methods could still determine the D/H ratio from a surface composed entirely of crystalline H2O-ice, deriving it for surfaces with a significant amorphous fraction may lead to severe underestimation of the true D/H ratio.
PreprintOptical Constants of Photochemical Haze Analogs in N2-CH4-CO Atmospheres from 0.4 to 28.6 {\mu}m
We present newly acquired FTIR and retrieved optical constants (N=n+ik) of laboratory-generated haze analogs from N2/CH4 and N2/CH4/CO gas mixtures under plasma discharge conditions.
PreprintRegime transitions of dynamos driven by fingering double-diffusive convection
Our results show that dynamo evolution is governed by a competition between Lorentz-force regulation and stratification-induced flow reorganisation.
Preprint with a published versionDesigning 3D transfers: application to Earth-Moon
In this paper, we propose a new method to design 3D transfers using a tangential velocity constraint for the burns, modeled using the overdetermined constraints technique based on the Theory of Functional Connections for an optimal search of solutions in a numerically efficient way.
PreprintExoplanet Atmosphere Spectral Sensitivity Analysis with PICASO: Jacobians, Linear-Gaussian Approximations, and Information Content
Here, we present a sensitivity analysis and retrieval diagnostic toolkit within the open-source code PICASO.
PreprintCode availableThe Dynamical Environment of Kepler-223 Planetary System
In this work, we re-examine the dynamical state of Kepler-223 by performing high-resolution N-body integrations and constructing detailed stability maps in the (a,e) phase space, we demonstrate that the system is locked in a deeper resonant state than previously thought.
Preprint with a published versionExoplanet Detection Techniques: Radial Velocity
This chapter serves as a comprehensive guide for understanding the capabilities and applications of the radial velocity method, equipping readers with the knowledge and resources to address their own scientific questions using this technique.
PreprintSearching for Massive Remnant Planetary System Hosts with White Dwarf Gaia XP Spectra
We present a selection of cool white dwarfs confirmed to be both massive and metal polluted, demonstrating that Gaia XP spectra can substantially expand the sample of white dwarf exoplanet hosts.
PreprintMarginalized planet-to-star radius ratio posteriors for low-SNR transiting planets via dimensionality reduction
We present a method that computes the marginalized posterior of the planet-to-star radius ratio while sampling only a lower-dimensional effective parameter space.
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