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Assembling the puzzle From Earths to Super-Earths Hitran to the rescue...

Assembling the puzzle From Earths to Super-Earths Hitran to the rescue... “ Good planets are hard to find ” Bracewell. Lisa Kaltenegger Harvard-Smithsonian Center for Astrophysics HITRAN Conf, June 22th 2008. Planets... The story so far.

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Assembling the puzzle From Earths to Super-Earths Hitran to the rescue...

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  1. Assembling the puzzle From Earths to Super-Earths Hitran to the rescue... “Good planets are hard to find”Bracewell Lisa Kaltenegger Harvard-Smithsonian Center for Astrophysics HITRAN Conf, June 22th 2008

  2. Planets... The story so far...

  3. New worlds in our sky... 300+ shadows of weird worlds...What can we tell?

  4. Fortney, 2007 Sasselov 2007 The KEY...Transiting planets Torres 2008

  5. Weather forecast on Giant exoplanets? Atmosphere by transits... HD189733b Tinetti et al 2007

  6. WHY ?

  7. The Pale Blue Dot Voyager image, 400 billion km away

  8. Earth IR-emission TES data; Christensen 2004 Kaltenegger, Traub, Jucks 2007 (ApJ)

  9. Line of Evidence LIFE ? What biota? What chemistry? What star ? HZ ? ATMOSPHERE INTERIOR Plate tectonics? Ocean/land? WHAT KIND Density ? (radius/mass) FORMATION Formation Models

  10. Line of Evidence SPECTRAL FINGERPRINT LIFE ? ATMOSPHERE INTERIOR FIND

  11. OUTLINE CODES Planet interior & outgassing add • Climate (Kasting, Segura, Pavlov) • Photochemistry (Segura, Kasting) • Radiative Transfer (Traub, Jucks) Cloud physics (CO2 & H2O) add Kaltenegger et al 2007

  12. Signs Of Life On An Earth-like Planet Needed for life Primordial; & bacteria product Plant product Bacteria Plant life Carbon dioxide Nitrous oxide observed Vegetation Ozone Water Methane Oxygen

  13. Selsis 2007

  14. Spectral features IR & Is there Take out ? Traub & Jucks, AGU, 2002; Des Marais et al. 2002, Selsis 2003, Kaltenegger 2007

  15. photochemistry Atmospheric escape Biological processing Geochemical recycling e. g. carbonate silicate cycle Outgassing Early or continuous

  16. LIFE LIFE

  17. The Test...The possibilities...Characterizing planets Selsis (data Kasting et al 93) Update Kaltenegger & Segura (prep)

  18. Habitable Zone... Goldilocks Zone Selsis, Kasting et al 2007; Kaltenegger & Selsis 2007

  19. CIS for Exoplanets: Spectral Fingerprints TPF-C New World Finder Paillet et al., in prep

  20. Earth part of the puzzle... & a universe full of possibilities Sontin et al 2007 Leger et al 2004

  21. How to make water from a H2-rich atmosphere ? Reduction of Fe-bearing silicates by H2 (Sasaki, 1990) For fO2≤ core formation H20/H2 ~ 0.1 (Solar nebula : 6 x 10-4 Delivery?) H2O vapor promotes greenhouse: Earth’s temp. as high as 4800 K

  22. Earth Evolution over geological time Kaltenegger et al 2007 ApJ

  23. Goldilocks ZoneGl 581c... HOT, Gl581d COLD Continuous habitable zone Selsis et al 2007, Kaltenegger et al 2008, Seager et al 2008, Miller-Ricci et al 2008,...

  24. Super Earth around M star 3400K Tidally locked planet 1: day (60%) night side (40%) 2: day (75%) night side (25%) 3: day (85%) night side (15%) Kaltenegger et al 2008 (in prep)

  25. Super Earth around M star 3400K Tidally locked planet (rapidely rotating planet comparison line (shown in grey)) • Scenario 3: high heat transport from day (85%) to night side (15%) Kaltenegger et al 2008 (in prep) CO2 O3 H2O CH4 H2O

  26. Transits... Pushing the limits Radius +/- ~ 0.06% Kaltenegger, Traub, Jucks 2008 (sub)

  27. Transits... Detecting habitable atmospheres Kaltenegger, Traub, Jucks 2008 (sub)

  28. Hitran Shopping list • Near-IR lines (CH4) • Line profile (especially wings - Transits) • Self broadening... Line broadening • High atm pressure (< 3 bar) • (= high gravity on Super-Earths) • Transits probe upper Earth atmosphere mainly • Warming and cooling of atmosphere • e.g. dense and early Earth atmospheres • …

  29. LIFE LIFE LIFE SUPER EARTHS... opportunity & challenge

  30. Habitabitity of Super Earths Gl581d Gl 581d: Earth Amtosphere, 2.63 bar, 1.8x Earth gravity. M star 3200K Scenario 1: no heat transfer day & night side (freeze out on dark side) Scenario 2: Planet rapidely rotating like Earth (same temperature day and night side) Scenario 3: Low heat transfer between day (75%) & night side (25%), no freeze out Kaltenegger et al. 2008 (in prep)

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