Re-Evaluating WASP-12b: Strong Emission at 2.315 micron, Deeper Occultations, and an Isothermal Atmosphere

Abstract

We revisit the atmospheric properties of the extremely hot Jupiter WASP-12b in light of several new developments. First, new narrowband (2.315 micron) secondary eclipse photometry that we present here, which exhibits a planet/star flux ratio of 0.45% +/- 0.06 %, corresponding to a brightness temperature of 3640 K +/- 230 K; second, recent Spitzer/IRAC and Hubble/WFC3 observations; and third, a recently observed star only 1" from WASP-12, which has diluted previous observations and which we further characterize here. We correct past WASP-12b eclipse measurements for the presence of this object, and we revisit the interpretation of WASP-12b's dilution-corrected emission spectrum. The resulting planetary emission spectrum is well-approximated by a blackbody, and consequently our primary conclusion is that the planet's infrared photosphere is nearly isothermal. Thus secondary eclipse spectroscopy is relatively ill-suited to constrain WASP-12b's atmospheric abundances, and transmission spectroscopy may be necessary to achieve this goal.

arXiv comment16 pages, 8 figures, 4 tables. v3: Contamination fraction and light curve both included in "Source" tarball

References in corpus (65)

• The chemical composition of the Sun
• Accurate masses and radii of normal stars: modern results and applications
• Shrinking binary and planetary orbits by Kozai cycles with tidal friction
• Color Transformations for the 2MASS Second Incremental Data Release
• Planetary Radii across Five Orders of Magnitude in Mass and Stellar Insolation: Application to Transits
• Achieving better than 1 minute accuracy in the Heliocentric and Barycentric Julian Dates
• The orbital motion, absolute mass, and high-altitude winds of exoplanet HD209458b
• Theoretical Transmission Spectra During Extrasolar Giant Planet Transits
• Obliquities of Hot Jupiter host stars: Evidence for tidal interactions and primordial misalignments
• Detection of Thermal Emission from an Extrasolar Planet
• An Infrared Spectroscopic Sequence of M, L and T Dwarfs
• The second US Naval Observatory CCD Astrograph Catalog (UCAC2)
• Formation of Hot Planets by a combination of planet scattering, tidal circularization, and Kozai mechanism
• New Grids of ATLAS9 Model Atmospheres
• Sodium Absorption From the Exoplanetary Atmosphere of HD189733b Detected in the Optical Transmission Spectrum
• The signature of orbital motion from the dayside of the planet tau Bootis b
• The Mauna Kea Observatories Near-Infrared Filter Set. II. Specifications for a New JHKL'M' Filter Set for Infrared Astronomy
• WASP-12b: The hottest transiting planet yet discovered
• A ground-based transmission spectrum of the super-Earth exoplanet GJ1214b
• The Statistics of Albedo and Heat Recirculation on Hot Exoplanets
• The Flat Transmission Spectrum of the Super-Earth GJ1214b from Wide Field Camera 3 on the Hubble Space Telescope
• High C/O Ratio and Weak Thermal Inversion in the Very Hot Atmosphere of Exoplanet WASP-12b
• Metals in the Exosphere of the Highly Irradiated Planet WASP-12b
• The Transit Light Curve Project. IX. Evidence for a Smaller Radius of the Exoplanet XO-3b
• The Stellar Populations of Praesepe and Coma Berenices
• Transmission Spectra of Three-Dimensional Hot Jupiter Model Atmospheres
• Low Resolution Spectral Templates For AGNs and Galaxies From 0.03 -- 30 microns
• Possible thermochemical disequilibrium in the atmosphere of the exoplanet GJ 436b
• Multi-Wavelength Constraints on the Day-Night Circulation Patterns of HD 189733b
• Improving Galactic Center Astrometry by Reducing the Effects of Geometric Distortion
• The Effect of Tidal Inflation Instability on the Mass and Dynamical Evolution of Extrasolar Planets with Ultra-Short Periods
• Properties of planets in binary systems. The role of binary separation
• A ground-based near-infrared emission spectrum of the exoplanet HD 189733b
• Thermal Phase Variations of WASP-12b: Defying Predictions
• Weighing The Non-Transiting Hot Jupiter Tau BOO b
• Light and Motion in SDSS Stripe 82: The Catalogues
• Irradiated Planets
• Phase-Dependent Properties of Extrasolar Planet Atmospheres
• Binarity of Transit Host Stars - Implications on Planetary Parameters
• On the Orbit of Exoplanet WASP-12b
• WASP-12b as a prolate, inflated and disrupting planet from tidal dissipation
• Constraining High Speed Winds in Exoplanet Atmospheres Through Observations of Anomalous Doppler Shifts During Transit
• On the Inference of Thermal Inversions in Hot Jupiter Atmospheres
• Near-infrared Thermal Emission from WASP-12b: detections of the secondary eclipse in Ks, H & J
• Spitzer Secondary Eclipses of WASP-18b
• High Resolution, Differential, Near-infrared Transmission Spectroscopy of GJ 1214b
• The Transit Light Curve project. XIV. Confirmation of Anomalous Radii for the Exoplanets TrES-4b, HAT-P-3b, and WASP-12b
• Near-Infrared Thermal Emission from TrES-3b: A Ks-band detection and an H-band upper limit on the depth of the secondary eclipse
• A new Search for Carbon Monoxide Absorption in the Transmission Spectrum of the Extrasolar Planet HD 209458b
• Day-side z'-band emission and eccentricity of Wasp-12b
• Ks-band detection of thermal emission and color constraints to CoRoT-1b: A low-albedo planet with inefficient atmospheric energy redistribution and a temperature inversion
• Ground-based detections of thermal emission from CoRoT-1b and WASP-12b
• Detection of Planetary Emission from the Exoplanet TrES-2 using Spitzer /IRAC
• Non-LTE Effects of Na I in the Atmosphere of HD209458b
• Non-Linearity Corrections and Statistical Uncertainties Associated with Near-Infrared Arrays
• Ground-based K-band detection of thermal emission from the exoplanet TrES-3b
• Non-Detection of L-band Line Emission from the Exo-Planet HD189733b
• High-precision photometry of WASP-12 b transits
• Explorations into the Viability of Coupled Radius-Orbit Evolutionary Models for Inflated Planets
• Orbital eccentricity of WASP-12 and WASP-14 from new radial-velocity monitoring with SOPHIE
• Ground-based, Near-infrared Exospectroscopy. II. Tentative Detection of Emission From the Extremely Hot Jupiter WASP-12b
• Non-LTE treatment of molecules in the photospheres of cool stars
• Near infrared spectroscopic search for the close orbiting planet HD 75289b
• Exoplanets transmission spectroscopy: accounting for eccentricity and longitude of periastron. Superwinds in the upper atmosphere of HD209458b?
• Spectroscopy of Putative Brown Dwarfs in Taurus

Cited by in corpus (89)

• emcee: The MCMC Hammer
• The imprint of exoplanet formation history on observable present-day spectra of hot Jupiters
• Spitzer Secondary Eclipses of the Dense, Modestly-irradiated, Giant Exoplanet HAT-P-20b Using Pixel-Level Decorrelation
• Extremely Irradiated Hot Jupiters: Non-Oxide Inversions, H- Opacity, and Thermal Dissociation of Molecules
• Model atmospheres of irradiated exoplanets: The influence of stellar parameters, metallicity, and the C/O ratio
• A Systematic Retrieval Analysis of Secondary Eclipse Spectra II: A Uniform Analysis of Eight Planets and Their C to O Ratios
• Global Climate and Atmospheric Composition of the Ultra-Hot Jupiter WASP-103b from HST and Spitzer Phase Curve Observations
• Exoplanetary Atmospheres - Chemistry, Formation Conditions, and Habitability
• HST hot Jupiter transmission spectral survey: evidence for aerosols and lack of TiO in the atmosphere of WASP-12b
• Observing transiting planets with JWST -- Prime targets and their synthetic spectral observations
• The Apparently Decaying Orbit of WASP-12
• Carbon monoxide and water vapor in the atmosphere of the non-transiting exoplanet HD 179949 b
• Transmission Spectroscopy of the Hot-Jupiter WASP-12b from 0.7 to 5 microns
• The Orbit of WASP-12b is Decaying
• Increased Heat Transport in Ultra-Hot Jupiter Atmospheres Through H${}_2$ Dissociation/Recombination
• Friends of Hot Jupiters II: No Correspondence Between Hot-Jupiter Spin-Orbit Misalignment and the Incidence of Directly Imaged Stellar Companions
• Exoplanet Transit Spectroscopy Using WFC3: WASP-12 b, WASP-17 b, and WASP-19 b
• Characterizing Transiting Planet Atmospheres through 2025
• Detection of molecular absorption in the dayside of exoplanet 51 Pegasi b?
• H2O abundances in the atmospheres of three hot Jupiters
• High temperature condensate clouds in super-hot Jupiter atmospheres
• Observations of Exoplanet Atmospheres
• Balancing the Energy Budget of Short-Period Giant Planets: Evidence for Reflective Clouds and Optical Absorbers
• Departure from the constant-period ephemeris for the transiting exoplanet WASP-12 b
• Probing the extreme planetary atmosphere of WASP-12b
• Spitzer observations of the thermal emission from WASP-43b
• Deciphering the Atmospheric Composition of WASP-12b: A Comprehensive Analysis of its Dayside Emission
• Where is the Water? Jupiter-like C/H ratio but strong H${}_2$O depletion found on $\tau$ Boötis b using SPIRou
• Spectra as Windows into Exoplanet Atmospheres
• Features in the Broadband Eclipse Spectra of Exoplanets: Signal or Noise?
• C/O Ratios of Stars with Transiting Hot Jupiter Exoplanets
• Statistical Characterization of Hot Jupiter Atmospheres using Spitzer's Secondary Eclipses
• Five key exoplanet questions answered via the analysis of 25 hot Jupiter atmospheres in eclipse
• Transit Timing Variation Measurements of WASP-12b and Qatar-1b: No Evidence for Additional Planets
• New chemical scheme for studying carbon-rich exoplanet atmospheres
• TEA: A Code for Calculating Thermochemical Equilibrium Abundances
• A Lucky Imaging search for stellar sources near 74 transit hosts
• WASP-8b: Characterization of a Cool and Eccentric Exoplanet with Spitzer
• Ground-Based Transit Spectroscopy of the Hot-Jupiter WASP-19b in the Near-Infrared
• WASP-12b and HAT-P-8b are Members of Triple Star Systems
• Giant Planets
• Warm Ice Giant GJ 3470b. I. A Flat Transmission Spectrum Indicates a Hazy, Low-methane, and/or Metal-rich Atmosphere
• Strict Upper Limits on the Carbon-to-Oxygen Ratios of Eight Hot Jupiters from Self-Consistent Atmospheric Retrieval
• Mass Loss from the Exoplanet WASP-12b Inferred from $\text{Spitzer}$ Phase Curves
• Carbon Dioxide in Exoplanetary Atmospheres: Rarely Dominant Compared to Carbon Monoxide and Water in Hot, Hydrogen-dominated Atmospheres
• Near-infrared Thermal Emission Detections of a number of hot Jupiters and the Systematics of Ground-based Near-infrared Photometry
• Atmospheric Retrieval of Exoplanets
• What are little worlds made of? Stellar abundances and the building blocks of planets
• A Comprehensive Reanalysis of $\text{Spitzer}$'s 4.5 $\mu$m Phase Curves, and the Phase Variations of the Ultra-hot Jupiters MASCARA-1b and KELT-16b
• The Very Low Albedo of WASP-12b From Spectral Eclipse Observations with $\text{Hubble}$
• Identifying new opportunities for exoplanet characterisation at high spectral resolution
• WTS-2 b: a hot Jupiter orbiting near its tidal destruction radius around a K-dwarf
• Ks band secondary eclipses of WASP-19b and WASP-43b with the Anglo-Australian Telescope
• Utilizing Small Telescopes Operated by Citizen Scientists for Transiting Exoplanet Follow-up
• The Hubble PanCET program: Transit and Eclipse Spectroscopy of the Strongly Irradiated Giant Exoplanet WASP-76b
• A Lucky Imaging search for stellar companions to transiting planet host stars
• The Dawes Review 3: The Atmospheres of Extrasolar Planets and Brown Dwarfs
• A 0.8-2.4 Micron Transmission Spectrum of the Hot Jupiter CoRoT-1b
• CO or no CO? Narrowing the CO abundance constraint and recovering the H2O detection in the atmosphere of WASP-127 b using SPIRou
• Examining the broadband emission spectrum of WASP-19b: A new z band eclipse detection
• Contamination from a nearby star cannot explain the anomalous transmission spectrum of the ultra-short period giant planet WASP-103b
• Colour-magnitude diagrams of transiting Exoplanets - II. A larger sample from photometric distances
• Assessing Spectra and Thermal Inversions due to TiO in Hot Jupiter Atmospheres
• ULTRACAM z'-band Detection of the Secondary Eclipse of WASP-12b
• Search for TiO and Optical Night-side Emission from the Exoplanet WASP-33b
• Lucky Imaging of transiting planet host stars with LuckyCam
• Observed spectral energy distribution of the thermal emission from the dayside of WASP-46b
• A temperature inversion in WASP-33b? Large Binocular Telescope occultation data confirm significant thermal flux at short wavelengths
• Ground-Based Transmission Spectroscopy with FORS2: A featureless optical transmission spectrum and detection of H${}_2$O for the ultra-hot Jupiter WASP-103b
• Retrieval of the dayside atmosphere of WASP-43b with CRIRES+
• Benchmark Tests for Markov Chain Monte Carlo Fitting of Exoplanet Eclipse Observations
• Spitzer IRAC Sparsely Sampled Phase Curve of the Exoplanet WASP-14b
• First Light of Engineered Diffusers at the Nordic Optical Telescope Reveal Time Variability in the Optical Eclipse Depth of WASP-12b
• Defocussed Transmission Spectroscopy: A potential detection of sodium in the atmosphere of WASP-12b
• Future Direct Spectroscopic Detection of Hot Jupiters with IGRINS
• On the ultraviolet anomalies of the WASP-12 and HD 189733 systems: Trojan satellites as a plasma source
• Storms or Systematics? The changing secondary eclipse depth of WASP-12b
• Atmospheric C/O Ratios of Sub-Neptunes with Magma Oceans: Homemade rather than Inherited
• Measuring the variability of directly imaged exoplanets using vector Apodizing Phase Plates combined with ground-based differential spectrophotometry
• Atmospheric Characterization of Hot Jupiter CoRoT-1 b Using the Wide Field Camera 3 on the Hubble Space Telescope
• Phase curve and variability analysis of WASP-12b using TESS photometry
• Colour-colour and colour-magnitude diagrams for Hot Jupiters
• The ExoGRAVITY project: using single mode interferometry to characterize exoplanets
• On the Dayside Atmosphere of WASP-12b
• Refined Ephemeris for Four Hot Jupiters using Ground-Based and TESS Observations
• BD-14 3065b (TOI-4987b): from giant planet to brown dwarf: evidence for deuterium burning in old age?
• Interpreting the atmospheric composition of exoplanets: sensitivity to planet formation assumptions
• The tidal quality of the hot Jupiter WASP-12b
• Re-evaluating Hot Jupiter WASP-12b: An Update