observational astronomy lecture 10 exoplanets Friday, November 22, 13 recap lecture 10 exoplanets Friday, November 22, 13 recap lecture 10 exoplanets Friday, November 22, 13 recap 52nm 170nm lecture 10 exoplanets Friday, November 22, 13 recap redshift longer wavelength => redder light wavelength increase as source moves away lecture 10 exoplanets Friday, November 22, 13 recap for small z (all of our labs): for small larger z the geometry of the universe must be taken into account! lecture 10 exoplanets Friday, November 22, 13 recap lecture 10 exoplanets Friday, November 22, 13 recap light curve (with noise) brightness time lecture 10 exoplanets Friday, November 22, 13 recap lecture 10 exoplanets Friday, November 22, 13 recap lecture 10 exoplanets Friday, November 22, 13 recap lecture 10 exoplanets Friday, November 22, 13 recap lecture 10 exoplanets Friday, November 22, 13 recap not all the matter shines: Dark matter Dark : no electromagnetic interaction - but yes gravitational interaction! atoms, regular matter: 4% Dark : what is it?? not electron protons neutrons lecture 10 exoplanets Friday, November 22, 13 recap image A lens lensed object image B observer lecture 10 exoplanets Friday, November 22, 13 lecture 10 exoplanets Friday, November 22, 13 lecture 10 exoplanets Friday, November 22, 13 lecture 10 exoplanets Friday, November 22, 13 lecture 10 exoplanets Friday, November 22, 13 study dark matter that lenses background galaxies lecture 10 exoplanets Friday, November 22, 13 study dark matter that lenses background galaxies study distant objects that would be too faint to be seen but are lensed lecture 10 exoplanets Friday, November 22, 13 exoplanets lecture 10 exoplanets Friday, November 22, 13 exoplanets cosmic pluralism lecture 10 exoplanets Friday, November 22, 13 Thales (700BC) Anaximander (700BC) Atomists: Democitus, Epicurus (400BC) lecture 10 exoplanets Friday, November 22, 13 De l'Infinito Universo et Mondi (On the Infinite Universe and Worlds, 1584) • holding opinions contrary to the Catholic faith and speaking against it and its ministers; • holding opinions contrary to the Catholic faith about the Trinity, divinity of Christ, and Incarnation; • holding opinions contrary to the Catholic faith pertaining to Jesus as Christ; • holding opinions contrary to the Catholic faith regarding the virginity of Mary • holding opinions contrary to the Catholic faith about both Transubstantiation and Mass; • claiming the existence of a plurality of worlds and their eternity; • believing in metempsychosis and in the transmigration of the human soul into brutes; • dealing in magics and divination. lecture 10 exoplanets Friday, November 22, 13 De l'Infinito Universo et Mondi (On the Infinite Universe and Worlds, 1584) • holding opinions contrary to the Catholic faith and speaking against it and its ministers; • holding opinions contrary to the Catholic faith about the Trinity, divinity of Christ, and Incarnation; • holding opinions contrary to the Catholic faith pertaining to Jesus as Christ; • holding opinions contrary to the Catholic faith regarding the virginity of Mary • holding opinions contrary to the Catholic faith about both Transubstantiation and Mass; • claiming the existence of a plurality of worlds and their eternity; • believing in metempsychosis and in the transmigration of the human soul into brutes; • dealing in magics and divination. lecture 10 exoplanets Friday, November 22, 13 I feel entirely at ease. When the sky was only a blue vault, with the stars nailed to it, the universe seemed small and narrow to me; I felt oppressed by it. Now that they've given infinitely greater breadth and depth to this vault . it seems to me that I breathe more freely, that I'm in a larger atmosphere, and certainly the universe has a greater magnificence (Hargreaves, 63). Bernard le Bovier de Fontenelle’s frontispiece, “Conversations on the Plurality of Worlds”, 1686 lecture 10 exoplanets Friday, November 22, 13 l 300 l 200 exoplanet discoveries l 100 l l l l l 1990 1995 2000 2005 2010 lecture 10 exoplanets Friday, November 22, 13 1990 Dr. Alexander Wolszczan first planet discovered Pulsar Timing Method around a pulsar the planets causes changes in the timing of the pulsar rotation, which is otherwise extremely regular lecture 10 exoplanets Friday, November 22, 13 NASA/JPL-Caltech/R. Hurt (SSC) lecture 10 exoplanets Friday, November 22, 13 Pulsar Timing Method - mass now 12 planetary systems, 15 planets, 2 multiple planet systems lecture 10 exoplanets Friday, November 22, 13 1995 51 Pegasi (51Peg) D. Letham Harvard/Smithsonian CfA the motion of the star around the system’s center of mass is detectable as a blu-redshift due to Doppler effect lecture 10 exoplanets Friday, November 22, 13 lecture 10 exoplanets Friday, November 22, 13 lecture 10 exoplanets Friday, November 22, 13 Radial Velocity Method lecture 10 exoplanets Friday, November 22, 13 Radial Velocity Method lecture 10 exoplanets Friday, November 22, 13 Astrometry Method lecture 10 exoplanets Friday, November 22, 13 1996 announcement of multiple planets orbiting the nearby star Lalande 21185 by George Gatewood ...later debunked now 402 planetary systems, 534 planets, 92 multiple planet systems lecture 10 exoplanets Friday, November 22, 13 Pulsar Timing Method - mass Radial Velocity - mass+inclination Astrometry - mass+inclination lecture 10 exoplanets Friday, November 22, 13 Transit Method lecture 10 exoplanets Friday, November 22, 13 Transit Method planetary transits lecture 10 exoplanets Friday, November 22, 13 Transit Method lecture 10 exoplanets Friday, November 22, 13 Transit Method lecture 10 exoplanets Friday, November 22, 13 1999 HD 209458 b D. Charbonneau Harvard/Smithsonian CfA Size comparison of HD 209458 b with Jupiter. 1.7% drop in HD 209458's brightness, lecture 10 exoplanets Friday, November 22, 13 1999 HD 209458 b D. Charbonneau Harvard/Smithsonian CfA Size comparison of HD 209458 b with Jupiter. 1.7% drop in HD 209458's brightness, now 321 planetary systems, 425 planets, 71 multiple planet systems lecture 10 exoplanets Friday, November 22, 13 Kepler mission 2010-2013 lecture 10 exoplanets Friday, November 22, 13 lecture 10 exoplanets Friday, November 22, 13 http://vimeo.com/19642643 lecture 10 exoplanets Friday, November 22, 13 Pulsar Timing Method - mass Radial Velocity - mass+inclination Astrometry - mass+inclination Transit - radius, distance+inclination lecture 10 exoplanets Friday, November 22, 13 Microlensing Method lecture 10 exoplanets Friday, November 22, 13 2002 OGLE: Andrzej Udalski, Marcin Kubiak and Michał Szymański the Optical Gravitational Lensing Experiment now 23 planetary systems, 25 planets, 2 multiple planet systems lecture 10 exoplanets Friday, November 22, 13 Pulsar Timing Method - mass Radial Velocity - mass+inclination Astrometry - mass+inclination Transit - radius, distance+inclination Microlensing - mass lecture 10 exoplanets Friday, November 22, 13 Pulsar Timing Method - mass Radial Velocity - mass+inclination Astrometry - mass+inclination Transit - radius, distance+inclination Microlensing - mass Timing variations - mass,distance+inclination of other planets in the system lecture 10 exoplanets Friday, November 22, 13 Direct Imaging Method 2005 Paul Kalas Farmalhaut b (now 12 imaged planets) lecture 10 exoplanets Friday, November 22, 13 Blue radial velocity Green transiting Orange microlensing Yellow timing Red direct imaging 1990 1995 2000 2005 2010 lecture 10 exoplanets Friday, November 22, 13 different methods explore different regions of parameter space: (bias) http://www.openexoplanetcatalogue.com/correlations.html lecture 10 exoplanets Friday, November 22, 13 Summary • exoplanets are discovered with indirect observatoional methods. we know of nearly 1000 exoplanets today • each methods gives its own incomplete set of information about the planets. • radial velocity surveys, so far the most prolific, use the doppler effect caused by the motion of a star around the center of mass of the system it hosts. astrometry looks at that motion directly, depending on the planet’s inclination either may be visible to us. • transits detect a periodic decrease in the apparent luminosity of a star due to obscuration by a planet crossing the star disk in its orbit, when aligned right for us to see it • gravitational lensing observes a rapid brightening of the star due to the lensing effect of a planet moving in the foreground • radial velocity & astrometry give mass convolved w/ inclination, & period • gravitational lensing, pulsar timing measure the mass of the planet • transits measure the size of the planet and the period • we are beginning now to image planets in infrared light; the brightness of the star must be obscured to do so lecture 10 exoplanets Friday, November 22, 13 Reading http://en.wikipedia.org/wiki/ Methods_of_detecting_extrasolar_planets and http://lcogt.net/spacebook/exoplanets read ALL sections: each describes a different method, but especially the transits and microlensing QA sections http://kepler.nasa.gov/education/resources/KeplerInBrief/ lecture 10 exoplanets Friday, November 22, 13.