KRONOS I: The $1-2.8\mu$m JWST Transmission Spectrum of the 23 Myr V1298 Tau c

Abstract

While recent JWST observations of mature super-Earths and sub-Neptunes have frequently revealed featureless transmission spectra, their inflated progenitors offer a unique window into understanding their primordial compositions. As part of the Keys to Revealing the Origin and Nature Of sub-neptune Systems (KRONOS) JWST program, we present the NIRISS/SOSS transmission spectrum of V1298 Tau c, a $\sim$23 Myr super-Earth progenitor orbiting a young Solar analog. We detect H${}_2$O in V1298 Tau c's atmosphere with a ${\log }_{10}$ volume mixing ratio of $-1.83_{-0.77}^{+0.68}$, but no additional molecules from these data alone. We find consistent results for the planetary atmospheric properties in both retrievals with and without informed priors on stellar heterogeneities based on the observed stellar spectrum. We infer an atmospheric metallicity [O/H] of $14.8_{-12.28}^{+56.0}\times$ the solar value. This metallicity is similar to literature measurements for other young planets, including its massive outer companion V1298~Tau~b. In contrast, this measured metallicity is systematically lower than the metallicities of mature planets of similar mass and temperature. Altogether, these results provide tentative but growing evidence that the exoplanet mass--metallicity relation evolves with planetary age.

arXiv commentAccepted for publication in The Astronomical Journal. 33 pages, 15 figures

References in corpus (128)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Array Programming with NumPy
• emcee: The MCMC Hammer
• The chemical composition of the Sun
• Gaia Data Release 2. Summary of the contents and survey properties
• MultiNest: an efficient and robust Bayesian inference tool for cosmology and particle physics
• Interstellar Dust Grains
• Multimodal nested sampling: an efficient and robust alternative to MCMC methods for astronomical data analysis
• X-ray spectral modelling of the AGN obscuring region in the CDFS: Bayesian model selection and catalogue
• The California-Kepler Survey. III. A Gap in the Radius Distribution of Small Planets
• Bayes in the sky: Bayesian inference and model selection in cosmology
• Planet Occurrence within 0.25 AU of Solar-type Stars from Kepler
• The false positive rate of Kepler and the occurrence of planets
• batman: BAsic Transit Model cAlculatioN in Python
• Fast and scalable Gaussian process modeling with applications to astronomical time series
• Kepler planets: a tale of evaporation
• The evaporation valley in the Kepler planets
• Atmospheric Escape from Hot Jupiters
• A Temperature and Abundance Retrieval Method for Exoplanet Atmospheres
• The Role of Core Mass in Controlling Evaporation: the Kepler Radius Distribution and the Kepler-36 Density Dichotomy
• The Mass-Metallicity Relation for Giant Planets
• ExoMol line lists IV: The rotation-vibration spectrum of methane up to 1500 K
• Sculpting the Valley in the Radius Distribution of Small Exoplanets as a by-product of Planet Formation: The Core-Powered Mass-Loss Mechanism
• The MUSCLES Treasury Survey I: Motivation and Overview
• The Transit Light Source Effect: False Spectral Features and Incorrect Densities for M-dwarf Transiting Planets
• A variationally computed line list for hot NH3
• Planetary population synthesis coupled with atmospheric escape: a statistical view of evaporation
• Early Release Science of the exoplanet WASP-39b with JWST NIRSpec PRISM
• ExoMol line lists III: An improved hot rotation-vibration line list for HCN and HNC
• Super-Earth Atmospheres: Self-Consistent Gas Accretion and Retention
• Early Release Science of the Exoplanet WASP-39b with JWST NIRSpec G395H
• The coronal X-ray - age relation and its implications for the evaporation of exoplanets
• A statistical test for Nested Sampling algorithms
• Early Release Science of the exoplanet WASP-39b with JWST NIRISS
• Mass-Metallicity Trends in Transiting Exoplanets from Atmospheric Abundances of H${}_2$O, Na, and K
• Evolutionary Analysis of Gaseous Sub-Neptune-Mass Planets with MESA
• Collaborative Nested Sampling: Big Data vs. complex physical models
• The Influence of Non-Uniform Cloud Cover on Transit Transmission Spectra
• The cosmic shoreline: the evidence that escape determines which planets have atmospheres, and what this may mean for Proxima Centauri b
• Signatures of the Core-Powered Mass-Loss Mechanism in the Exoplanet Population: Dependence on Stellar Properties and Observational Predictions
• The atmospheric circulation of a nine-hot Jupiter sample: Probing circulation and chemistry over a wide phase space
• High Tide or Riptide on the Cosmic Shoreline? A Water-Rich Atmosphere or Stellar Contamination for the Warm Super-Earth GJ~486b from JWST Observations
• HAZMAT I: The Evolution of Far-UV and Near-UV Emission from Early M Stars
• Comoving stars in Gaia DR1: An abundance of very wide separation co-moving pairs
• Four newborn planets transiting the young solar analog V1298 Tau
• Retrieval of planetary and stellar properties in transmission spectroscopy with Aura
• The Stagger-grid: A grid of 3D stellar atmosphere models - IV. Limb darkening coefficients
• Effect of stellar spots on high-precision transit light-curve
• The Transit Light Source Effect II: The Impact of Stellar Heterogeneity on Transmission Spectra of Planets Orbiting Broadly Sun-like Stars
• The nature and origins of sub-Neptune size planets
• A broadband thermal emission spectrum of the ultra-hot Jupiter WASP-18b
• Results of the ROTOR-program. II. The long-term photometric variability of weak-line T Tauri stars
• Placing the spotted T Tauri star LkCa 4 on an HR diagram
• Flare Statistics for Young Stars from a Convolutional Neural Network Analysis of $\text{TESS}$ Data
• Atmosphere Origins for Exoplanet Sub-Neptunes
• A High Internal Heat Flux and Large Core in a Warm Neptune Exoplanet
• Why are the K dwarfs in the Pleiades so Blue?
• Stealing the Gas: Giant Impacts and the Large Diversity in Exoplanet Densities
• Transit Signatures of Inhomogeneous Clouds on Hot Jupiters: Insights From Microphysical Cloud Modeling
• Double Trouble: Two Transits of the Super-Earth GJ 1132 b Observed with JWST NIRSpec G395H
• Limb-darkening and exoplanets II: Choosing the Best Law for Optimal Retrieval of Transit Parameters
• JWST/NIRISS reveals the water-rich "steam world" atmosphere of GJ 9827 d
• A warm Neptune's methane reveals core mass and vigorous atmospheric mixing
• HAZMAT. IV. Flares and Superflares on Young M Stars in the Far Ultraviolet
• A warm Jupiter-sized planet transiting the pre-main sequence star V1298 Tau
• Awesome SOSS: Transmission Spectroscopy of WASP-96b with NIRISS/SOSS
• The Planetary Mass-Radius Relation and its Dependence on Orbital Period as Measured by Transit Timing Variations and Radial Velocities
• Birth and fate of hot-Neptune planets
• Rapid contraction of giant planets orbiting the 20 million-years old star V1298 Tau
• Aurora: A Generalised Retrieval Framework for Exoplanetary Transmission Spectra
• How planets grow by pebble accretion. III. Emergence of an interior composition gradient
• Comparison of the power-2 limb-darkening law from the Stagger-grid to Kepler light curves of transiting exoplanets
• A Benchmark JWST Near-Infrared Spectrum for the Exoplanet WASP-39b
• TESS Hunt for Young and Maturing Exoplanets (THYME) IV: Three small planets orbiting a 120 Myr-old star in the Pisces--Eridanus stream
• X-ray irradiation and evaporation of the four young planets around V1298 Tau
• Ultraviolet-Selected Field and Pre-Main-Sequence Stars Towards Taurus and Upper Scorpius
• HAZMAT VI: The Evolution of Extreme Ultraviolet Radiation Emitted from Early M Star
• The Near Infrared Imager and Slitless Spectrograph for the James Webb Space Telescope -- III. Single Object Slitless Spectroscopy
• Constraining mornings & evenings on distant worlds: a new semi-analytical approach and prospects with transmission spectroscopy
• Overfitting Affects the Reliability of Radial Velocity Mass Estimates of the V1298 Tau Planets
• A Relationship Between Stellar Age and Spot Coverage
• To cool is to keep: Residual H/He atmospheres of super-Earths and sub-Neptunes
• Hints of a sulfur-rich atmosphere around the 1.6 R${}_{\oplus }$ Super-Earth L98-59 d from JWST NIRSpec G395H transmission spectroscopy
• TOI-2076 and TOI-1807: Two young, comoving planetary systems within 50 pc identified by TESS that are ideal candidates for further follow-up
• Uncovering the true periods of the young sub-Neptunes orbiting TOI-2076
• Coupled Thermal and Compositional Evolution of Photo Evaporating Planet Envelopes
• H-alpha and Ca II Infrared Triplet Variations During a Transit of the 23 Myr Planet V1298 Tau c
• Assessment of Supervised Machine Learning for Atmospheric Retrieval of Exoplanets
• An Aligned Orbit for the Young Planet V1298 Tau b
• Escaping Helium and a Highly Muted Spectrum Suggest a Metal-Enriched Atmosphere on Sub-Neptune GJ3090b from JWST Transit Spectroscopy
• Aura-3D: A Three-dimensional Atmospheric Retrieval Framework for Exoplanet Transmission Spectra
• Toward Robust Corrections for Stellar Contamination in JWST Exoplanet Transmission Spectra
• Hot Jupiter Diversity and the Onset of TiO/VO Revealed by a Large Grid of Non-Grey Global Circulation Models
• Evidence for Morning-to-Evening Limb Asymmetry on the Cool Low-Density Exoplanet WASP-107b
• Unbiasing the density of TTV-characterised sub-Neptunes: Update of the mass-radius relationship of 34 Kepler planets
• Multiple Clues for Dayside Aerosols and Temperature Gradients in WASP-69 b from a Panchromatic JWST Emission Spectrum
• V1298 Tau with TESS: Updated Ephemerides, Radii, and Period Constraints from a Second Transit of V1298 Tau e
• Monitoring the young planet host V1298 Tau with SPIRou: planetary system and evolving large-scale magnetic field
• Ground-based Optical Transmission Spectroscopy of the Nearby Terrestrial Exoplanet LTT 1445Ab
• HAZMAT. VII. The Evolution of Ultraviolet Emission with Age and Rotation for Early M Dwarf Stars
• Exoplanet Interior Retrievals: core masses and metallicities from atmospheric abundances
• The Thermal Emission Spectrum of the Nearby Rocky Exoplanet LTT 1445A b from JWST MIRI/LRS
• The metal-poor atmosphere of a Neptune/Sub-Neptune planet progenitor
• Insufficient evidence for DMS and DMDS in the atmosphere of K2-18 b. From a joint analysis of JWST NIRISS, NIRSpec, and MIRI observations
• The NewEra model grid
• Planet Mass and Metallicity: The Exoplanets and Solar System Connection
• Catwoman: A transit modelling Python package for asymmetric light curves
• Challenges in the detection of gases in exoplanet atmospheres
• Limb darkening measurements from TESS and Kepler light curves of transiting exoplanets
• Sub-Neptunes Are Drier Than They Seem: Rethinking the Origins of Water-Rich Worlds
• First Comparative Exoplanetology Within a Transiting Multi-planet System: Comparing the atmospheres of V1298 Tau b and c
• Magma ocean interactions can explain JWST observations of the sub-Neptune TOI-270 d
• A Panchromatic Characterization of the Evening and Morning Atmosphere of WASP-107 b: Composition and Cloud Variations, and Insight into the Effect of Stellar Contamination
• Tracing the formation and migration history: molecular signatures in the atmosphere of misaligned hot Jupiter WASP-94Ab using JWST NIRSpec/G395H
• A young progenitor for the most common planetary systems in the Galaxy
• Diversity in the haziness and chemistry of temperate sub-Neptunes
• Blowin' in the non-isothermal wind: core-powered mass loss with hydrodynamic radiative transfer
• Cloudy mornings and clear evenings on a gas giant exoplanet
• Do Young Suns Produce Frequent, Massive CMEs? Results from Five-year Dedicated Optical Observations of EK Draconis and V889 Hercules
• Unraveling the non-equilibrium chemistry of the temperate sub-Neptune K2-18 b
• An Analytic Characterization of the Limb Asymmetry -- Transit Time Degeneracy
• GEMS JWST: Transmission spectroscopy of TOI-5205b reveals significant stellar contamination and a metal-poor atmosphere
• Heavy element enriched atmospheres and where they are born
• The SPACE Program. I. The featureless spectrum of HD 86226 c challenges sub-Neptune atmosphere trends
• Coupled Thermal-Chemical Evolution Models of Sub-Neptunes Reveal Atmospheric Signatures of Their Formation Location
• A Comprehensive Analysis of the Panchromatic Transmission Spectrum of the Hot-Saturn WASP-96 b: Nondetection of Haze, Possible Sodium Limb Asymmetry, Stellar Characterization, and Formation History
• Quantifying the Impact of Starspot-Crossing Events on Retrieved Parameters from Transit Lightcurves
• The atmosphere of K2-18 b: The role of hazes, clouds and photoelectrons