TOI-712: a system of adolescent mini-Neptunes extending to the habitable zone

Abstract

As an all-sky survey, NASA's $TESS$ mission is able to detect the brightest and rarest types of transiting planetary systems, including young planets that enable study of the evolutionary processes that occur within the first billion years. Here, we report the discovery of a young, multi-planet system orbiting the bright K4.5V star, TOI-712 ($V=10.838$, $M_{\star }=0.733_{-0.025}^{+0.026}{M}_{\odot }$, $R_{\star }=0.674\pm 0.016R_{\odot }$, $T_{\mathrm{eff}}=4622_{-60}^{+61}$ K). From the $TESS$ light curve, we measure a rotation period of 12.48 days, and derive an age between about $500$ Myr and 1.1 Gyr. The photometric observations reveal three transiting mini-Neptunes ($R_b=2.049_{-0.080}^{+0.12}{R}_{\oplus }$, $R_c=2.701_{-0.082}^{+0.092}{R}_{\oplus }$, $R_d=2.474_{-0.082}^{+0.090}{R}_{\oplus }$), with orbital periods of $P_b=9.531$ days, $P_c=51.699$ days, and $P_d=84.839$ days. After modeling the three-planet system, an additional Earth-sized candidate is identified, TOI-712.05 ($P=4.32$ days, $R_P=0.81\pm 0.11R_{\oplus }$). We calculate that the habitable zone falls between 0.339 and 0.844 au (82.7 and 325.3 days), placing TOI-712 d near its inner edge. Among planetary systems harboring temperate planets, TOI-712 ($T=9.9$) stands out as a relatively young star bright enough to motivate further characterization.

arXiv comment20 pages, 11 figures, 5 tables, submitted to AAS Journals

References in corpus (109)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• Astropy: A Community Python Package for Astronomy
• The NumPy array: a structure for efficient numerical computation
• Gaia Data Release 2. Summary of the contents and survey properties
• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• The Gaia mission
• Modules for Experiments in Stellar Astrophysics (MESA)
• Modules for Experiments in Stellar Astrophysics (MESA): Giant Planets, Oscillations, Rotation, and Massive Stars
• Modules for Experiments in Stellar Astrophysics (MESA): Binaries, Pulsations, and Explosions
• MESA Isochrones and Stellar Tracks (MIST). I: Solar-Scaled Models
• Intrinsic Colors, Temperatures, and Bolometric Corrections of Pre-Main Sequence Stars
• Gaia Data Release 2: The astrometric solution
• MESA Isochrones and Stellar Tracks (MIST) 0: Methods for the construction of stellar isochrones
• The K2 Mission: Characterization and Early results
• Habitable Zones Around Main-Sequence Stars: New Estimates
• Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics
• Las Cumbres Observatory Global Telescope Network
• batman: BAsic Transit Model cAlculatioN in Python
• Ages for illustrative field stars using gyrochronology: viability, limitations and errors
• Kepler Presearch Data Conditioning I - Architecture and Algorithms for Error Correction in Kepler Light Curves
• Kepler planets: a tale of evaporation
• Architecture and Dynamics of Kepler's Candidate Multiple Transiting Planet Systems
• Architecture of Kepler's Multi-transiting Systems: II. New investigations with twice as many candidates
• The TESS Input Catalog and Candidate Target List
• AstroImageJ: Image Processing and Photometric Extraction for Ultra-Precise Astronomical Light Curves (Expanded Edition)
• AstroImageJ: Image Processing and Photometric Extraction for Ultra-Precise Astronomical Light Curves
• Habitable Zones Around Main-Sequence Stars: Dependence on Planetary Mass
• Overview of the Kepler Science Processing Pipeline
• Probabilistic Forecasting of the Masses and Radii of Other Worlds
• A Framework for Prioritizing the TESS Planetary Candidates Most Amenable to Atmospheric Characterization
• BANYAN. XI. The BANYAN $\Sigma$ multivariate Bayesian algorithm to identify members of young associations within 150 pc
• Core-powered mass loss and the radius distribution of small exoplanets
• Improving the Efficiency of Markov Chain Monte Carlo for Analyzing the Orbits of Extrasolar Planets
• The TESS Objects of Interest Catalog from the TESS Prime Mission
• Stellar Flares from the First Tess Data Release: Exploring a New Sample of M-dwarfs
• The Kepler Catalog of Stellar Flares
• Kepler Data Validation I -- Architecture, Diagnostic Tests, and Data Products for Vetting Transiting Planet Candidates
• Limb and gravity-darkening coefficients for the TESS satellite at several metallicities, surface gravities, and microturbulent velocities
• Almost All of Kepler's Multiple Planet Candidates are Planets
• Eccentricity from transit photometry: small planets in Kepler multi-planet systems have low eccentricities
• CHIRON - A Fiber Fed Spectrometer for Precise Radial Velocities
• Compositional imprints in density-distance-time: a rocky composition for close-in low-mass exoplanets from the location of the valley of evaporation
• Densities and Eccentricities of 139 Kepler Planets from Transit Time Variations
• Real-time processing of the imaging data from the network of Las Cumbres Observatory Telescopes using BANZAI
• Kepler Data Validation II -- Transit Model Fitting and Multiple-Planet Search
• Transit Least Squares: Optimized transit detection algorithm to search for periodic transits of small planets
• A planet within the debris disk around the pre-main-sequence star AU Microscopii
• Architecture of Planetary Systems Based on Kepler Data: Number of Planets and Coplanarity
• Planets around evolved intermediate-mass stars. I. Two substellar companions in the open clusters NGC 2423 and NGC 4349
• Untangling the Galaxy I: Local Structure and Star Formation History of the Milky Way
• Ten years of speckle interferometry at SOAR
• A Neptune-sized transiting planet closely orbiting a 5-10-million-year-old star
• A First Comparison of Kepler Planet Candidates in Single and Multiple Systems
• Zodiacal Exoplanets in Time (ZEIT) III: A short-period planet orbiting a pre-main-sequence star in the Upper Scorpius OB Association
• When Do Stalled Stars Resume Spinning Down? Advancing Gyrochronology with Ruprecht 147
• TESS Hunt for Young and Maturing Exoplanets (THYME): A planet in the 45 Myr Tucana-Horologium association
• Zodiacal Exoplanets In Time (ZEIT) I: A Neptune-sized planet orbiting an M4.5 dwarf in the Hyades Star Cluster
• A Catalog of Kepler Habitable Zone Exoplanet Candidates
• The Kepler Dichotomy among the M Dwarfs: Half of Systems Contain Five or More Coplanar Planets
• Zodiacal Exoplanets in Time (ZEIT) IV: seven transiting planets in the Praesepe cluster
• The Distribution of Transit Durations for Kepler Planet Candidates and Implications for their Orbital Eccentricities
• Two 'b's in the Beehive: The Discovery of the First Hot Jupiters in an Open Cluster
• A Temporary Epoch of Stalled Spin-Down for Low-Mass Stars: Insights from NGC 6811 with Gaia and Kepler
• Flare Statistics for Young Stars from a Convolutional Neural Network Analysis of $\text{TESS}$ Data
• Searching for Young M Dwarfs with GALEX
• TESS Spots a Compact System of Super-Earths around the Naked-Eye Star HR 858
• Searching for Planets in the Hyades V: Limits on Planet Detection in the Presence of Stellar Activity
• HD 285507b: An Eccentric Hot Jupiter in the Hyades Open Cluster
• EXOFASTv2: A public, generalized, publication-quality exoplanet modeling code
• TESS Hunt for Young and Maturing Exoplanets (THYME) II: A 17 Myr Old Transiting Hot Jupiter in the Sco-Cen Association
• On the Frequency of Potential Venus Analogs from Kepler Data
• Measuring the Recoverability of Close Binaries in Gaia DR2 with the Robo-AO Kepler Survey
• Extended stellar systems in the solar neighborhood - II. Discovery of a nearby 120° stellar stream in Gaia DR2
• TESS Hunt for Young and Maturing Exoplanets (THYME) III: a two-planet system in the 400 Myr Ursa Major Group
• Architectures of Exoplanetary Systems. III: Eccentricity and Mutual Inclination Distributions of AMD-stable Planetary Systems
• The lithium depletion boundary and the age of the Hyades cluster
• TESS reveals that the nearby Pisces-Eridanus stellar stream is only 120 Myr old
• Zodiacal Exoplanets in Time (ZEIT) VI: a three-planet system in the Hyades cluster including an Earth-sized planet
• Zodiacal Exoplanets in Time (ZEIT) V: A Uniform Search for Transiting Planets in Young Clusters Observed by K2
• A New Look at an Old Cluster: The Membership, Rotation, and Magnetic Activity of Low-Mass Stars in the 1.3-Gyr-Old Open Cluster NGC 752
• A warm Jupiter-sized planet transiting the pre-main sequence star V1298 Tau
• Zodiacal Exoplanets in Time (ZEIT) VIII: A Two Planet System in Praesepe from K2 Campaign 16
• A Criterion for the Onset of Chaos in Systems of Two Eccentric Planets
• Flare Rates, Rotation Periods. and Spectroscopic Activity Indicators of a Volume-Complete Sample of Mid-to-Late M dwarfs within 15 Parsecs
• K2 Discovers a Busy Bee: An Unusual Transiting Neptune Found in the Beehive Cluster
• The secondary eclipses of WASP-19b as seen by the ASTEP 400 telescope from Antarctica
• TESS Hunt for Young and Maturing Exoplanets (THYME) V: A Sub-Neptune Transiting a Young Star in a Newly Discovered 250 Myr Association
• Two young planetary systems around field stars with ages between 20-320 Myr from TESS
• Ultraviolet-Selected Field and Pre-Main-Sequence Stars Towards Taurus and Upper Scorpius
• Evolution of the Exoplanet Size Distribution: Forming Large Super-Earths Over Billions of Years
• A Number of Nearby Moving Groups may be Fragments of Dissolving Open Clusters
• Differential rotation and meridional flow on the lower zero age main sequence: Reynolds stress versus baroclinic flow
• A Low-Mass Exoplanet Candidate Detected By $K2$ Transiting the Praesepe M Dwarf JS 183
• Orbital Dynamics of Multi-Planet Systems with Eccentricity Diversity
• TOI-2076 and TOI-1807: Two young, comoving planetary systems within 50 pc identified by TESS that are ideal candidates for further follow-up
• Three Small Planets Transiting a Hyades Star
• Habitable Zone Dependence on Stellar Parameter Uncertainties
• Zodiacal Exoplanets in Time (ZEIT) VII: A Temperate Candidate Super-Earth in the Hyades Cluster
• K2-264: A transiting multi-planet system in the Praesepe open cluster
• Thermalizing a telescope in Antarctica: Analysis of ASTEP observations
• The warm Neptunes around HD 106315 have low stellar obliquities
• The GAPS Programme at TNG XXVIII -- A pair of hot-Neptunes orbiting the young star TOI-942
• HAZMAT. V. The Ultraviolet and X-ray Evolution of K Stars
• Predicting the Yield of Potential Venus Analogs from TESS and their Potential for Atmospheric Characterization
• HAZMAT. VIII. A Spectroscopic Analysis of the Ultraviolet Evolution of K Stars: Additional Evidence for K Dwarf Rotational Stalling in the First Gigayear
• Orbital Stability and Precession Effects in the Kepler-89 System
• Eclipsing binaries in the open cluster Ruprecht 147. III: The triple system EPIC 219552514 at the main-sequence turnoff
• Resolving Close Encounters: Stability in the HD 5319 and HD 7924 Planetary Systems
• Evidence for a Non-Dichotomous Solution to the Kepler Dichotomy: Mutual Inclinations of Kepler Planetary Systems from Transit Duration Variations

Cited by in corpus (5)

• A 1.55 R${}_{\oplus }$ habitable-zone planet hosted by TOI-715, an M4 star near the ecliptic South Pole
• The PLATO field selection process. II. Characterization of LOPS2, the first long-pointing field
• TOI-1801 b: A temperate mini-Neptune around a young M0.5 dwarf
• Dynamical masses of two young transiting sub-Neptunes orbiting HD 63433
• The GAPS Programme at TNG. LXV. Precise density measurement of TOI-1430 b, a young planet with an evaporating atmosphere