ExtrasolarExtrasolar PlanetsPlanets:: UsheringUshering inin thethe EraEra ofof ComparativeComparative ExoplanetologyExoplanetology
A. Sozzetti INAF – Osservatorio Astrofisico di Torino
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 Detection/CharacterizationDetection/Characterization
• Detection (Visible): •Characterization (Visible/IR): - Doppler spectroscopy (95%) - Transit timing - Transit photometry (20%) - Transmission spectroscopy - Gravitational microlensing (2%) - Rossiter -McLaughlin effect - Pulsar/pulsation timing (1.5%) - Reflected light - imaging (1.5%) - Infrared emission
986 Exoplanets known today, in 750 systems
168 in multiple -planet systems
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 TheThe HistoricalHistorical PerspectivePerspective
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 ComparativeComparative ExoplanetologyExoplanetology
• Orbital elements, mass distributions, multiplicity
• Correlations between planetary parameters and between planet characteristics and frequencies and the properties of the stellar hosts
• Internal structure, atmospheric composition and circulation
Putting our Solar System in Context!
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 DirectDirect Imaging:Imaging: AA FamilyFamily PortraitPortrait
2M1207 DH Tau AB Pic SCR1845 CHXR 73
GJ 758 CT Cha 1RXJS609 GQ Lup
Wide orbit PMCs : - low mass KM stars - q = 0.02 – 0.2 or ∆ > 200 AU
Fomalhaut Hr8799 Beta Pic Closer PMCs : - A4V-A5V massive primaries - q < 0.005 ; ∆ = 8 - 120 AU - CS Disk signatures
Ref: Chauvin et al. 04; Itoh et al. 05; Chauvin et al. 05; Biller et al. 05; Luhman et al. 06; Thalmann et al. 09; Lafrenière et al. 08; Neuhauser et al. 05; Schmidt et al. 09 ; Lagrange et al. 10; Kalas et al. 08; Marois et al. 08,10...
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 Direct Imaging: Companion Nature?
Planet Single-band photometry Stellar properties: d & age Evolutionary models (Luminosity - Mass) . β Pictoris b, ∆J = 10.6+-0.3 mag, . 12 Myr @ 19.3 pc,
. Mass = 7 – 8 Mjup (“Hot-Start”models)
> However , uncertainties in the model predictions Field Rotation > Dependence: formation mechanisms , gas accretion shock & initial conditions
Marley et al. 07; Mordasini et al. 12 Bonnefoy et al. 12
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 PrecisionPrecision RVs:RVs: PushingPushing thethe MassMass LimitsLimits
Deuterium -burning limit
HD 114762b
Gap?
Alpha CenBb
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 ‘‘HabitableHabitable ’’ LowLow --MassMass Planets?Planets?
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 αα CenCen Bb:Bb: TheThe FirstFirst EarthEarth --((minimum)massminimum)mass PlanetPlanet
460 RVs!
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 TheThe ‘‘StellarStellar NoiseNoise ’’ ChallengeChallenge
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 PlanetaryPlanetary Systems:Systems: EmergingEmerging PropertiesProperties
• Second planet detection rate 17%, including trends > 30%
• >20 RV systems with at least three detected planets, and up to 7!
• Great dynamical diversity (hierarchical systems, secular interactions, mean -motion resonances)
• Inferences on the likelihood of formation and survival of rocky planets in the Habitable Zone
• Different orbital elements distribution functions
• Differences in distributions for low -mass systems and systems with gas giants
• Different behaviour of fp vs. M * and [Fe/H] in single - and multiple -planet systems
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 TheThe PlanetPlanet –– HostHost StarStar ConnectionConnection
Sozzetti et al. 2009 Johnson et al. 2010
Critical tests of competing giant planet formation models
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 TransitingTransiting Planets:Planets: AA TreasureTreasure TroveTrove
• Learn about the history of planet migration
• Learn about the architecture of multiple systems
• Learn about the physical structure and composition of exoplanets
• Learn about the structure, chemistry, and dynamics of atmospheres
Tens of ground -based surveys, two highly successful space projects
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 Measuring Spin-Orbit Alignment
Ohta, Taruya, & Suto (2005); Gaudi & Winn (2007)
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 RR--MM EffectEffect Measurements:Measurements: StatusStatus
• Spin-orbit angles have been measured for 35+ exoplanets • Many have highly tilted orbits, some are retrograde • Tilted orbits are especially common for hot (massive) stars • Disk migration cannot be the whole story for hot Jupiters • Migration via few-body dynamics? • The tradition of exoplanetary surprises continues • Even close binary stars can be misaligned!
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 TheThe KeplerKepler ‘‘RevolutionRevolution ’’
3558 78
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 MultipleMultiple --PlanetPlanet CandidateCandidate SystemsSystems
100s ’ of ‘flat ’ systems, the vast majority with small radii
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 ExoplanetsExoplanets InteriorsInteriors andand AtmospheresAtmospheres
Burrows et al. 2007
THEORETICAL INPUT - internal properties - structure and heat content - atmospheric properties
OBSERVABLES Evolutionary properties as a function of irradiation conditions and orbital distance: - mass, - radius, - temperature, - age, - emergent spectrum, composition
Burrows 2005
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 TheThe MassMass --RadiusRadius RelationshipRelationship
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 Transits Allow Studies of the Atmospheres That Are Not (Yet) Possible for Non -Transiting Planets
Secondary Eclipse See thermal radiation and reflected light from planet disappear and reappear
Transit See radiation from star transmitted through the planet’s atmosphere
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 PhasePhase LightcurvesLightcurves
HAT-P7b observed by Kepler (Borucki et al, 2010)
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 Swain et al ., 2008; Madhu & Seager, 2009; Danielski et al., 2013; Beaulieu et al., 2010; XCIXBurrows Congresso et al., SIF 2011; Deming et al., 2013; Tinetti et al., 2010; CrouzetSISSA-Trieste, et al., 27 2012 Sep 2013 GJGJ 1214b1214b
A ‘cool ’ Super -Earth Around an M4.5 dwarf
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013 TheThe Future:Future: ComparativeComparative PlanetologyPlanetology Observations • Space -borne transit surveys (Kepler, TESS, PLATO): frequency of terrestrial habitable planets around G -K dwarfs, contributions from ground -based experiments (APACHE, NGTS) for M dwarf samples
• SPHERE/GPI, ELTs , JWST, coronagraphs/interferometers and other IR telescopes in space ( EChO ): characterization of giant planets ’ atmospheres and search for ‘bio -markers ’ on Earth -sized planets around nearby stars
• Doppler surveys (HARPS/ -N,ESPRESSO), astrometry (Gaia): very low masses, very long periods, wider ranges of the hosts ’ spectral types and ages, characterization of multiple systems. Theory
• Self -consistent modeling of formation and migration processes, and improved predictions (correlations, population synthesis ) • 3-d modeling of realistic disk environment • Probabilistic vs. deterministic approach • Better input physics for planet interiors and atmospheres
XCIX Congresso SIF SISSA-Trieste, 27 Sep 2013