The Occurrence of Rocky Habitable Zone Planets Around Solar-Like Stars from Kepler Data

Abstract

We present occurrence rates for rocky planets in the habitable zones (HZ) of main-sequence dwarf stars based on the Kepler DR25 planet candidate catalog and Gaia-based stellar properties. We provide the first analysis in terms of star-dependent instellation flux, which allows us to track HZ planets. We define ${\eta }_{\oplus }$ as the HZ occurrence of planets with radius between 0.5 and 1.5 $R_{\oplus }$ orbiting stars with effective temperatures between 4800 K and 6300 K. We find that ${\eta }_{\oplus }$ for the conservative HZ is between $0.37_{-0.21}^{+0.48}$ (errors reflect 68\% credible intervals) and $0.60_{-0.36}^{+0.90}$ planets per star, while the optimistic HZ occurrence is between $0.58_{-0.33}^{+0.73}$ and $0.88_{-0.51}^{+1.28}$ planets per star. These bounds reflect two extreme assumptions about the extrapolation of completeness beyond orbital periods where DR25 completeness data are available. The large uncertainties are due to the small number of detected small HZ planets. We find similar occurrence rates using both a Poisson likelihood Bayesian analysis and Approximate Bayesian Computation. Our results are corrected for catalog completeness and reliability. Both completeness and the planet occurrence rate are dependent on stellar effective temperature. We also present occurrence rates for various stellar populations and planet size ranges. We estimate with $95\%$ confidence that, on average, the nearest HZ planet around G and K dwarfs is about 6 pc away, and there are about 4 HZ rocky planets around G and K dwarfs within 10 pc of the Sun.

To appear in The Astronomical Journal

References in corpus (25)

• The K2 Mission: Characterization and Early results
• Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics
• Most 1.6 Earth-Radius Planets are not Rocky
• Habitable Zones Around Main-Sequence Stars: Dependence on Planetary Mass
• A stellar-mass-dependent drop in planet occurrence rates
• Was Venus the First Habitable World of our Solar System?
• Exoplanet population inference and the abundance of Earth analogs from noisy, incomplete catalogs
• The Kepler Follow-Up Observation Program. I. A Catalog of Companions to Kepler Stars from High-Resolution Imaging
• Strong Dependence of the Inner Edge of the Habitable Zone on Planetary Rotation Rate
• Revisited Mass-Radius relations for exoplanets below 120 Earth masses
• The Gaia-Kepler Stellar Properties Catalog. II. Planet Radius Demographics as a Function of Stellar Mass and Age
• A Statistical Reconstruction of the Planet Population Around Kepler Solar-Type Stars
• A Catalog of Kepler Habitable Zone Exoplanet Candidates
• Searching the Entirety of Kepler Data. II. Occurrence Rate Estimates for FGK Stars
• Scaling K2. I. Revised Parameters for 222,088 K2 Stars and a K2 Planet Radius Valley at 1.9 $R_{\oplus }$
• Accounting for Incompleteness due to Transit Multiplicity in Kepler Planet Occurrence Rates
• The Densities of Planets in Multiple Stellar Systems
• Unresolved Binary Exoplanet Host Stars Fit as Single Stars: Effects on the Stellar Parameters
• 3D climate modeling of Earth-like extrasolar planets orbiting different types of host stars
• Measuring Transit Signal Recovery in the Kepler Pipeline IV: Completeness of the DR25 Planet Candidate catalog
• Architectures of Exoplanetary Systems. II: An Increase in Inner Planetary System Occurrence Toward Later Spectral Types for Kepler's FGK Dwarfs
• The impact of stripped cores on the frequency of Earth-size planets in the habitable zone
• Reliability Correction is Key for Robust Kepler Occurrence Rates
• Sensitivity Analyses of Exoplanet Occurrence Rates from Kepler and Gaia
• Comparing Approximate Bayesian Computation with the Poisson-Likelihood Method for Exoplanet Occurrence Rates

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• The New Generation Planetary Population Synthesis (NGPPS). IV. Planetary systems around low-mass stars
• Large Interferometer For Exoplanets (LIFE): I. Improved exoplanet detection yield estimates for a large mid-infrared space-interferometer mission
• The CARMENES search for exoplanets around M dwarfs -- Planet occurrence rates from a subsample of 71 stars
• The NewAthena mission concept in the context of the next decade of X-ray astronomy
• Atmospheres of Rocky Exoplanets
• The Breakthrough Listen Search For Intelligent Life Near the Galactic Center I
• Large Interferometer For Exoplanets (LIFE): III. Spectral resolution, wavelength range and sensitivity requirements based on atmospheric retrieval analyses of an exo-Earth
• Large Interferometer For Exoplanets (LIFE): V. Diagnostic potential of a mid-infrared space-interferometer for studying Earth analogs
• The Kepler Giant Planet Search. I: A Decade of Kepler Planet-host Radial Velocities from W. M. Keck Observatory
• Stellar surface inhomogeneities as a potential source of the atmospheric signal detected in the K2-18 b transmission spectrum
• The Case for Technosignatures: Why They May Be Abundant, Long-lived, Highly Detectable, and Unambiguous
• Mapping the exo-Neptunian landscape. A ridge between the desert and savanna
• Bioverse: A Comprehensive Assessment of the Capabilities of Extremely Large Telescopes to Probe Earth-like O${}_2$ Levels in Nearby Transiting Habitable Zone Exoplanets
• Predicting the Exoplanet Yield of the TESS Prime and Extended Missions Through Years 1-7
• Plausible constraints on the range of bulk terrestrial exoplanet compositions in the Solar neighbourhood
• A framework for the architecture of exoplanetary systems. I. Four classes of planetary system architecture
• Super-Earths and Earth-like Exoplanets
• The Demographics of Kepler's Earths and super-Earths into the Habitable Zone
• A Second Earth-Sized Planet in the Habitable Zone of the M Dwarf, TOI-700
• Scaling K2. IV. A Uniform Planet Sample for Campaigns 1-8 and 10-18
• Large Interferometer For Exoplanets (LIFE): VI. Detecting rocky exoplanets in the habitable zones of Sun-like stars
• Variability due to climate and chemistry in observations of oxygenated Earth-analogue exoplanets
• Forming Iron-rich Planets with Giant Impacts
• Transit least-squares survey IV. Earth-like transiting planets expected from the PLATO mission
• Planets larger than Neptune have elevated eccentricities
• Bioverse: a simulation framework to assess the statistical power of future biosignature surveys
• Large Interferometer For Exoplanets (LIFE): IX. Assessing the Impact of Clouds on Atmospheric Retrievals at Mid-Infrared Wavelengths with a Venus-Twin Exoplanet
• PlatoSim: An end-to-end PLATO camera simulator for modelling high-precision space-based photometry
• On the Possibility of an Artificial Origin for `Oumuamua
• TOI-179: a young system with a transiting compact Neptune-mass planet and a low-mass companion in outer orbit
• A Star-sized Impact-Produced Dust Clump in the Terrestrial Zone of the HD 166191 System
• Atmospheric Dynamics of a Near Tidally Locked Earth-Size Planet
• In Search of the Edge: A Bayesian Exploration of the Detectability of Red Edges in Exoplanet Reflection Spectra
• Eta-Earth Revisited II: Deriving a Maximum Number of Earth-like Habitats in the Galactic Disk
• Planetesimals Around Stars with TESS (PAST): II. An M Dwarf "Dipper" Star with a Long-Lived Disk in the TESS Continuous Viewing Zone
• Postulating Exoplanetary Habitability via a Novel Anomaly Detection Method
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• Earth as an Exoplanet. III. Using Empirical Thermal Emission Spectra as an Input for Atmospheric Retrieval of an Earth-twin Exoplanet
• Milankovitch Cycles for a Circumstellar Earth-analog within $\alpha$ Centauri-like Binaries
• Polarized Signatures of a Habitable World: Comparing Models of an Exoplanet Earth with Visible and Near-infrared Earthshine Spectra
• Flux-Limited Diffusion Approximation Models of Giant Planet Formation by Disk Instability. II. Quadrupled Spatial Resolution
• Revising Properties of Planet-host Binary Systems II: Apparent Near-Earth Analog Planets in Binaries Are Often Sub-Neptunes
• Pursuing Truth: Improving Retrievals on Mid-Infrared Exo-Earth Spectra with Physically Motivated Water Abundance Profiles and Cloud Models
• Quantifying the Classification of Exoplanets: in Search for the Right Habitability Metric
• Extended habitability of exoplanets due to subglacial water
• Contemporaneous Observations of $H\alpha$ Luminosities and Photometric Amplitudes for M Dwarfs
• Infrared and Optical Detectability of Dyson Spheres at White Dwarf Stars
• Small and Close-In Planets are Uncommon Around A-type Stars
• Kepler-102: Masses and Compositions for a Super-Earth and Sub-Neptune Orbiting an Active Star
• Relative occurrence rates of terrestrial planets orbiting FGK stars
• The Potential of Detecting Nearby Terrestrial Planets in the HZ with Different Methods
• Earth-like planets hosting systems: Architecture and properties
• Elemental Abundances of Kepler Objects of Interest in APOGEE DR17
• Takeout and Delivery: Erasing the Dusty Signature of Late-stage Terrestrial Planet Formation
• Characterization of low-mass companions to $\text{Kepler}$ objects of interest observed with APOGEE-N
• What if we find nothing? Bayesian analysis of the statistical information of null results in future exoplanet habitability and biosignature surveys
• A Bayesian Monte Carlo assessment of orbital stability in the late stages of planetary system formation
• UV Spectral Characterization of Low-Mass Stars With AstroSat UVIT for Exoplanet Applications: The Case Study of HIP 23309
• Earth-like planet predictor: A machine learning approach
• Predicting the Dominant Formation Mechanism of Multi-Planetary Systems
• Continuous Habitable Zones: Using Bayesian Methods to Prioritize Characterization of Potentially Habitable Worlds
• The Implications of 'Oumuamua on Panspermia
• Modelling the Milky Way's exoplanet population based on cosmological galaxy simulations
• Undetected past contacts with technological species: implications for technosignature science
• Challenges in focal plane and telescope calibration for High-Precision Space Astrometry
• An Independent Search for Small Long-period Planets in Kepler Data I: Detection Pipeline
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• L 98-59: a Benchmark System of Small Planets for Future Atmospheric Characterization
• What the Solar System Can Teach Us About Rocky Exoplanets
• A preliminary exploration of the effects of baseline length for the LIFE space mission
• Exploring Long-period Architectures: Four New Planet Candidates from Kepler with Periods >342 days
• Searching for technosignatures in exoplanetary systems with current and future missions
• Friends and Foes: Conditional Occurrence Rates of Exoplanet Companions and their Impact on Radial Velocity Follow-up Surveys
• Exoplanet transit search at the detection limit: detection and false alarm vetting pipeline