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Extrasolar Planets: Past, Present, and Future. The Formation of Planetary Systems Heretic’s Approach to Solar System FormationFForm. Alan P. Boss Carnegie Institution of Washington. A Decade of Extrasolar Planets Around Normal Stars Space Telescope Science Institute, Baltimore, Maryland
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Extrasolar Planets: Past, Present, and Future The Formation of Planetary Systems Heretic’s Approach to Solar System FormationFForm Alan P. Boss Carnegie Institution of Washington A Decade of Extrasolar Planets Around Normal Stars Space Telescope Science Institute, Baltimore, Maryland May 2, 2005
The President’s Vision for U.S.Space Exploration (January 2004) B. Space Exploration Beyond Low Earth Orbit [Mars and other destinations]: * Conduct advanced telescope searches for Earth-like planets and habitable environments around other stars
HD 209458b Charbonneau et al., 2000
Microlensing detection with Warsaw 1.3m telescope, Las Campanas - 2004
Spitzer Space Telescope - first direct detection of a planet’s light - 2005
GQ Lup b – 1 Myr-old gas giant planet at 100 AU? (Neuhauser et al. 2005)
Extrasolar Planet Discovery Space brown dwarfs gas giant planets
http://www.dtm.ciw.edu/boss/iauindex.html IAU Working Group on Extrasolar Planets Groupe de Travail sur les planètes extra-solaires Members of Working Group (2003-2006) Chair (and Web Page Master): Alan BossMembers: Paul Butler, William Hubbard, Philip Ianna, Martin Kürster, Jack Lissauer, Michel Mayor, Karen Meech, Francois Mignard, Alan Penny, Andreas Quirrenbach, Jill Tarter, Alfred Vidal-Madjar Charge The WGESP is charged with acting as a focal point for research on extrasolar planets and organizing IAU activities in the field, including reviewing techniques and maintaining a list of identified planets. The details of the Terms of Reference are available. Definition of a "planet" The WGESP has developed a Working Definition of a "planet", subject to change as we learn more about the population of very low mass companions. List of Planets The WGESP has developed a Working List of extrasolar planet candidates, subject to revision. In most cases, the orbital inclination of these objects is not yet determined, which is why most should still be considered candidate planets.
metallicity-period correlation (2004) high Z low Z
Highest Metallicities Correlation: Migration or Formation? * Higher metallicity higher opacity hotter disk midplane higher sound speed (cs ) thicker disk (h) higher disk kinematic viscosity (n = a cs h) shorter time scale for Type II inward migration more short period giant planets * Uncertain magnitude of migration effect, but goes in the right direction to explain the correlation * Migration consistent with absence of short-period giants in low-metallicity globular cluster 47 Tuc * Migration consistent with long-period pulsar giant planet in M4 globular cluster (1/30 solar [Fe/H])
Discovery space with Neptune-mass planets Discovery space with latest discoveries added prior lowest m sin i
Neptune-mass, but what composition? [Need to discover 10 or more so that at least one will transit its star] -mass
Discovery space with Neptune-mass planets and their siblings Discovery space with latest discoveries added Mu Ara 55 Cnc
G. W. Wetherill, 1996, Icarus, 119, 219-238. Assuming surface density proportional to 1/radius, rock surface density of 9.3 g cm-2 at 1 AU should be increased by a factor of about 7 to account for rock/ice surface density needed at 5 AU of 25 g cm-2 to form Jupiter by core accretion (Inaba et al. 2003) 3 Earth masses 1 Earth mass Since mass of the terrestrial planets is roughly proportional to the surface density of solids, raising the solid surface density by a factor of about 7 should result in the formation of rocky planets with masses as high as about 21 Earth masses
Normal Jupiter and Saturn Jupiter only, mass x 3 Jupiter only, eccentricity = 0.4 Jupiter & Saturn, both mass x 3 Jupiter normal, Saturn mass x 3 Jupiter & Saturn, both mass/3 1.0 0.6 0.7 0.8 0.5 0.7 0.1 0.2 0.4 0.0 0.0 0.0 0.3 0.6 0.4 0.8 0.9 0.9 Habitable Planets per SystemChambers 2003[defined as terrestrial planets with masses greater that 1/3 that of Earth and Earth-like orbits] Giant Planet Formation Time: 0 Myr 3Myr 10Myr Giant Planet System Configuration:
NASA’s Space Interferometry Mission Space Interferometry Mission • Salient Features • 3 parallel Michelson Stellar Interferometers • 10 meter baseline • Visible wavelength • Launch Vehicle: Space Shuttle or EELV • Earth-trailing solar orbit • 5 year mission life with 10 year goal • SIM is a JPL, Caltech, Lockheed Martin, NGST, and SIM Science Team partnership • Science • Perform a search for other planetary systems by surveying 2000 nearby stars for astrometric signatures of planetary companions • Survey a sample of 200 nearby stars for orbiting planets down to terrestrial-type masses • Improve best current catalog of star positions by >100x and extend to fainter stars to allow extension of stellar knowledge to include our entire galaxy • Study dynamics and evolution of stars and star clusters in our galaxy to understand how our galaxy was formed and how it will evolve. • Calibrate luminosities of important stars and cosmological distance indicators to improve our understanding of stellar processes and to measure precise distance in the distant universe
Discovery space for extrasolar planetsby ground-based Doppler spectroscopy and by space-based astrometry (SIM)
Earth as seen by TES on Mars Global Surveyor