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Are there Planets outside the Solar System ? First answer : 1992 Discovery of the first Extra-Solar Planet around the pulsar PSR1257+12 (Wolszczan &Frail) Are there Planets moving around other Sun-like stars ? The EXO Planet: 51 Peg b Mass: M sin i = 0.468 m_Jup semi-major axis: a = 0.052 AU period: p = 4.23 days eccentricity: e = 0 a of Mercury: 0.387 AU Discovered by: Michel Mayor Didier Queloz Status of Observations 292 Extra-solar planetary systems 337 Planets near other solar-type stars 33 Mulitple planetary systems 43 Planets in binaries Multi-planetary systems Binaries Single Star and Single Planetary Systems Interesting Questions How frequent are other planetary systems ? Are they like our Solar System (no. of planets, masses, radii, albedos, orbital paramenters , …. ) What type of environments do they have? (atmospheres, magnetosphere, rings, … ) How do they form and evolve ? How do these features depend on the type of the central star (mass, chemical composition, age, binarity, … ) ? 55 Cancri 5 Planeten bei 55 Cnc: 55Cnc d -- the only known Jupiter-like planet in Jupiterdistance Binary: a_binary= 1000 AU Extra-solare Planeten ca. 130 Planeten entdeckt massereich enge (~Mjup) Umlaufbahnen Radialgeschwindigkeits- messungen Mass distribution Facts about Extra-Solar Planetary Systems: Only 28% of the detected planets have masses < 1 Jupitermass About 33% of the planets are closer to the host-star than Mercury to the Sun Nearly 60% have eccentricities > 0.2 And even 40% have eccentricities > 0.3 Distribution of the detected Extra-Solar Planets Mercury Earth Mars Venus Jupiter Target Stars for Darwin/TPF 315 stars M 10 pc K G Lifetime A F Temperature Sources of uncertainty in parameter fits: the unknown value of the orbital line-of-sight inclination i allows us to determine from radial velocities measurements only the lower limit of planetary masses; the relative inclination ir between planetary orbital planes is usually unknown. In most of the mulitple-planet systems, the strong dynamical interactions between planets makes planetary orbital parameters found – using standard two-body keplerian fits – unreliable (cf. Eric Bois) All these leave us a substantial available parameter space to be explored in order to exclude the initial conditions which lead to dynamically unstable configurations Major catastrophe in less than 100000 years SEMI-MAJOR AXIS 8.00 4.00 0.00 0 20000 40000 TIME (yr) 60000 (S. Ferraz-Mello, Numerical Methods Chaos Indicators: (FLI) Long-term numerical integration: C. Froeschle, R.Gonczi, E. Lega (1996) Stability-Criterion: Fast Lyapunov Indicator MEGNO RLI Helicity Angle LCE No close encounters within the Hill‘ sphere (i)Escape time (ii) Study of the eccentricity: maximum eccentricity Multi-planetary systems Binaries Single Star and Single Planetary Systems OGLE 06-109L Planet b: (0.71 +/-0.08 MJ) a=2.3 +/-0.2 AU e= ? P = 1825 (+/- 365) d Planet c: (0.27 +/- 0.03 MJ) a = 4.6 (+/-0.5) AU e = 0.11 i = 59 deg P = 5100 (+/-730) d www.univie.ac.at/adg/exostab/ ExoStab appropriate for single-star single-planet system - Stability of an additional planet - Stability of the habitable zone (HZ) - Stability of an additional planet with repect to the HZ Stability of an additional planet known parameters of system: mass of star [M_sun]: 0.5 mass of giant planet [M_jup]: 0.21 semi-major axis of giant planet [AU]: 4.6 eccentricity of giant planet: 0.11 +/- error of eccentricity: 0.05 newly discovered planet: Probable range of semi-major axis for the new planet: semi-major axis of planet [AU]: 2.3 +/- error of semi-major axis: 0.2 Results of the Exocatalogue (Sandor et al., 2007) The EXOCATALOGUE: http://www.univie.ac.at/adg/ Details: Sándor, Zs., Süli, A., Érdi, B., Pilat-Lohinger, E. and Dvorak, R.: "A Stability Catalogue of the Habitable zones in Extrasolar Planetary Systems", Monthly Notices of the Royal Astronomical Society (MNRAS), 2006 Habitable Zone Zone around a star where liquid water can exist on the surface of a terrestial-like planet This zone depends on: the spectraltype , the mass , the age, …. of the star the orbit of the planet the mass, the composition, the atmosphere , ……of the planet the parameters of other planets in this system (mass, orbit, …) Size of the habitable zone of a planetary system based on the definition given by Kasting et al. (1993). Types of Habitable Zones: (1) Hot-Jupiter type (2) Solar system type (3)+(4) giant planet type: habitable moon or trojan planet Stability maps Inner region (Solar system type) Outer region (Hot-Jupiter-type) Computations distance star-planet: 1 AU variation of - a_tp:[0.1,0.9] [1.1,4] AU - e_gp: 0 – 0.5 - M_gp: 0 and 180 deg - M_tp: [0, 315] deg Dynamical model: restricted 3 body problem Methods: (i) Chaos Indicator: - FLI (Fast Lyapunov) - RLI (Relative Lyapunov) (ii) Long-term computations - e-max ANIMATION How to use the catalogue HD114729: m_p=0.82 [Mjup] (0.93 [Msun]) a_p= 2.08 AU e_p=0.31 m=0.001 HZ: 0.7 – 1.3 AU m = 0.005 HD10697: (1.15 Msun) m_p= 6.12 [Mjup] a_p = 2.13 AU e_p = 0.11 HZ: 0.85 – 1.65 AU