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Extrasolar planets Telluric planets Une planète s’évapore Jovian Planets Giant gaseous planets Une planète s’évapore Solar system Une planète s’évapore Giordano Bruno (Nola 1548 – Roma 1600) «..l’infinito, universo e mondi innumerabili.» «…un Sole Nero inghiottirà nello spazio il sole, la luna, e tutti pianeti che ruotano intorno al sole" "Ad un corpo di dimensione infinita non può essere attribuito né un centro né un confine” "L'uomo viaggerà nel cosmo e dal cosmo apprenderà il giorno della sua fine” (De l'Infinito Universo et Mondi) “…. le stelle sono infinite e sono soli lontanissimi attorno ai quali girano pianeti e alcuni di questi mondi sono abitati da esseri intelligenti.” Extrasolar planets (up to October 2014) 900 800 Number of planets 700 600 500 400 300 200 100 0 1998 2000 2002 2004 2006 2008 Year of discovery 2010 2012 2014 Planets in the dwarf star Gliese 581 Distance: 22 light years Planets in the dwarf star Gliese 581 Extrasolar planet M1207b Distance: 52 pc 3-20 times the mass of Jupiter Distance from the star: 7.8 distance Jupiter - Sun Direct detection Two main difficulties : 1 – A tiny angular separation 2 – A huge contrast in luminosity Sun – Jupiter at 4 light years = 4 arcsec Sun – Jupiter at 100 light years = 0.15 arcsec Sun – Earth at 100 light years = 0.03 arcsec Sun – Earth at 100 parsec = 0.01 arcsec The star is up to 10 billion times brighter than the planet The star is up to 10 billion times brighter than the planet A solution: the method used by Le Verrier for the discovery of Neptune: the gravitational perturbation induced by the planet Gravitational perturbation induced by Jupiter on the Sun Period : 11.9 years Distance : 5.2 AU Velocity : 13 km/s Period : 11.9 years Distance : 0.005 AU Velocity : 12 m/s Jupiter orbit C.M. Solar motion Center of mass Dynamical effects • Astrometry • Radial velocity λ/δλ=100000 —> 3 km/s not enough ! Jupiter - Sun ! Amplitude = 12.5 m/s Period = 11.9 years Earth - Sun ! Amplitude = 0.1 m/s Period = 1 year Sensitive to short periods and more massive planets ! Gravitational microlensing 32 candidates up to now Une planète s’évapore OGLE 2005-BLG-071Lb ~ 2.7 MJ planet at ~ 2.2 / 3.7 AU Une planète s’évapore Occultation or transit Evaporation of Hot-Jupiters Eclipse 4/01/2011 & ISS Crédit: Thierry Legault Transit photometry star planet Brightness Brillance Une planète s’évapore Time Transit probability Edge-on orbit (i=90o) Face-on orbit (i=0o) The first transiting planet: Osiris French mission COROT COROT-7 NASA mission Kepler Kepler-10b Period: 0.84 days Mass: 4.5 ME Radius:1.42 RE Une planète s’évapore Infrared light curve of HD189733A+b September 29, 2014 1822 planets 1137 planetary systems 467 multiple planet systems 574 by radial velocity 1147 transiting 32 by microlensing 51 by direct imaging Extrapolation: several hundreds million of Jovian extrasolar planets in the Milky Way with periods of 5 or fewer days Sizes of planets (February 2014) 800 Number of planets 600 400 200 0 Jupiter size Neptune size Super-Earth size Earth size Present: atmospheres Future: bio signatures Une planète s’évapore
