Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-23T13:43:51.515Z Has data issue: false hasContentIssue false
  • English
  • Français

Runaway greenhouse effect on exomoons due to irradiation from hot, young giant planets

Published online by Cambridge University Press:  14 January 2014

R. Heller  and
R. Barnes
R. Heller*
Affiliation:
Department of Physics and Astronomy, McMaster University, 1280 Main Street West, Hamilton (ON) L8S 4M1, Canada
R. Barnes
Affiliation:
Department of Astronomy, University of Washington, Seattle, WA 98195, USA Virtual Planetary Laboratory, Box 351580, Seattle, WA 98195, USA
*
e-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

The Kepler space telescope has proven capable of detecting transits of objects almost as small as the Earth's Moon. Some studies suggest that moons as small as 0.2 Earth masses can be detected in the Kepler data by transit timing variations and transit duration variations of their host planets. If such massive moons exist around giant planets in the stellar habitable zone (HZ), then they could serve as habitats for extraterrestrial life. While earlier studies on exomoon habitability assumed the host planet to be in thermal equilibrium with the absorbed stellar flux, we here extend this concept by including the planetary luminosity from evolutionary shrinking. Our aim is to assess the danger of exomoons to be in a runaway greenhouse state due to extensive heating from the planet. We apply pre-computed evolution tracks for giant planets to calculate the incident planetary radiation on the moon as a function of time. Added to the stellar flux, the total illumination yields constraints on a moon's habitability. Ultimately, we include tidal heating to evaluate a moon's energy budget. We use a semi-analytical formula to parameterize the critical flux for the moon to experience a runaway greenhouse effect. Planetary illumination from a 13-Jupiter-mass planet onto an Earth-sized moon at a distance of ten Jupiter radii can drive a runaway greenhouse state on the moon for about 200 million years (Myr). When stellar illumination equivalent to that received by Earth from the Sun is added, then the runaway greenhouse holds for about 500 Myr. After 1000 Myr, the planet's habitable edge has moved inward to about six Jupiter radii. Exomoons in orbits with eccentricities of 0.1 experience strong tidal heating; they must orbit a 13-Jupiter-mass host beyond 29 or 18 Jupiter radii after 100 Myr (at the inner and outer boundaries of the stellar HZ, respectively), and beyond 13 Jupiter radii (in both cases) after 1000 Myr to be habitable. If a roughly Earth-sized, Earth-mass moon would be detected in orbit around a giant planet, and if the planet–moon duet would orbit in the stellar HZ, then it will be crucial to recover the orbital history of the moon. If, for example, such a moon around a 13-Jupiter-mass planet has been closer than 20 Jupiter radii to its host during the first few hundred million years at least, then it might have lost substantial amounts of its initial water reservoir and be uninhabitable today.

Keywords

astrobiology– celestial mechanics– planets and satellites: general– radiation mechanisms: general
Type
Research Article
Information
International Journal of Astrobiology , Volume 14 , Issue 2: SPECIAL ISSUE: EXOPLANET , April 2015 , pp. 335 - 343
Copyright
Copyright © Cambridge University Press 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Awiphan, S. & Kerins, E. (2013). Mon. Not. R. Astron. Soc. 432, 2549.CrossRefGoogle Scholar
Baraffe, I., Chabrier, G., Allard, F. & Hauschildt, P.H. (1998). Astron. Astrophy. 337, 403.Google Scholar
Baraffe, I., Chabrier, G., Barman, T.S., Allard, F. & Hauschildt, P.H. (2003). Astron. Astrophy. 402, 701.Google Scholar
Barclay, T. et al. (2013). Nature 494, 452.Google Scholar
Barnes, R. & Heller, R. (2013). Astrobiology 13, 279.CrossRefGoogle Scholar
Barnes, R. et al. (2013). Astrobiology 13, 225.Google Scholar
Běhounková, M., Tobie, G., Choblet, G. & Čadek, O. (2012). Icarus 219, 655.Google Scholar
Canup, R.M. & Ward, W.R. (2006). Nature 441, 834.Google Scholar
Cassidy, T.A., Mendez, R., Arras, P., Johnson, R.E. & Skrutskie, M.F. (2009). Astrophy. J. 704, 1341.Google Scholar
Darwin, G.H. (1879). Phil. Trans. R. Soc. 170, 447 (repr. Scientific Papers, Cambridge, Vol. II, 1908)Google Scholar
Darwin, G.H. (1880). R. Soc. Lond. Phil. Trans. Ser. I 171, 713.Google Scholar
Debes, J.H. & Sigurdsson, S. (2007). Astrophy. J. 668, L167.CrossRefGoogle Scholar
Dole, S.H. (1964). Habitable Planets for Man, 1st ed., Biaisdell Pub. Co., New York.Google Scholar
Domingos, R.C., Winter, O.C. & Yokoyama, T. (2006). Mon. Not. R. Astron. Soc. 373, 1227.CrossRefGoogle Scholar
Efroimsky, M. & Makarov, V.V. (2013). Astrophy. J. 764, 26.Google Scholar
Ferraz-Mello, S., Rodríguez, A. & Hussmann, H. (2008). Celest. Mech. Dyn. Astron. 101, 171.Google Scholar
Forgan, D. & Kipping, D. (2013). Mon. Not. R. Astron. Soc. 432, 2994.CrossRefGoogle Scholar
Fortney, J.J., Marley, M.S. & Barnes, J.W. (2007). Astrophy. J. 659, 1661.Google Scholar
Goldreich, P. & Soter, S. (1966). Icarus 5, 375.Google Scholar
Greenberg, R. (2009). Astrophy. J. 698, L42.Google Scholar
Hartman, J.D. et al. (2013). Astrophy. J, submitted, arXiv: 1308.2937.Google Scholar
Heller, R. (2012). Astron. Astrophy. 545, L8.Google Scholar
Heller, R. & Barnes, R. (2013). Astrobiology 13, 18.Google Scholar
Heller, R. & Zuluaga, J.I. (2013). Astrophy. J. 776, L33.Google Scholar
Heller, R., Leconte, J. & Barnes, R. (2011). Astron. Astrophy. 528, A27.Google Scholar
Heller, R. et al. (2013). Astrobiology (in preparation).Google Scholar
Heller, R. et al. (2014). Formation, habitability and detection of extrasolar moons Astrobiology submitted.Google Scholar
Henning, W.G., O'Connell, R.J. & Sasselov, D.D. (2009). Astrophy. J. 707, 1000.CrossRefGoogle Scholar
Hinkel, N.R. & Kane, S.R. (2013). Astrophy. J. 774, 27.Google Scholar
Hut, P. (1981). Astron. Astrophy. 99, 126.Google Scholar
Jackson, B., Greenberg, R. & Barnes, R. (2008). Astrophy. J. 681, 1631.Google Scholar
Kaltenegger, L. (2010). Astrophy. J. 712, L125.Google Scholar
Kasting, J.F. (1988). Icarus 74, 472.Google Scholar
Kasting, J.F., Whitmire, D.P. & Reynolds, R.T. (1993). Icarus 101, 108.Google Scholar
Kipping, D.M. (2009a). Mon. Not. R. Astron. Soc. 392, 181.Google Scholar
Kipping, D.M. (2009b). Mon. Not. R. Astron. Soc. 396, 1797.Google Scholar
Kipping, D.M. (2011). Mon. Not. R. Astron. Soc. 416, 689.Google Scholar
Kipping, D.M., Fossey, S.J. & Campanella, G. (2009). Mon. Not. R. Astron. Soc. 400, 398.Google Scholar
Kipping, D.M., Bakos, G.Á., Buchhave, L., Nesvorný, D. & Schmitt, A. (2012). Astrophy. J. 750, 115.Google Scholar
Kipping, D.M. et al. (2013a). Astrophy. J. 777, 134.CrossRefGoogle Scholar
Kipping, D.M. et al. (2013b). Astrophy. J. 770, 101.Google Scholar
Kopparapu, R.K. et al. (2013). Astrophy. J. 765, 131.Google Scholar
Lammer, H. (2013). Origin and Evolution of Planetary Atmospheres. SpringerBriefs in Astronomy.CrossRefGoogle Scholar
Leconte, J. & Chabrier, G. (2013). Nat. Geosci. 6, 347.Google Scholar
Leconte, J., Chabrier, G., Baraffe, I. & Levrard, B. (2010). Astron. Astrophy. 516, A64.Google Scholar
Lewis, K.M. (2013). Mon. Not. R. Astron. Soc. 430, 1473.Google Scholar
Mordasini, C. (2013). Astron. Astrophy. 558, A113.CrossRefGoogle Scholar
Moutou, C. et al. (2011). Astron. Astrophy. 527, A63.CrossRefGoogle Scholar
Ogihara, M. & Ida, S. (2012). Astrophy. J. 753, 60.Google Scholar
Ojakangas, G.W. & Stevenson, D.J. (1986). Icarus 66, 341.Google Scholar
Peale, S.J., Cassen, P. & Reynolds, R.T. (1979). Science 203, 892.Google Scholar
Pierrehumbert, R.T. (2010). Principles of Planetary Climate. Cambridge University Press, Cambridge, UK.Google Scholar
Porco, C.C. et al. (2006). Science 311, 1393.Google Scholar
Reynolds, R.T., McKay, C.P. & Kasting, J.F. (1987). Adv. Space Res. 7, 125.CrossRefGoogle Scholar
Sartoretti, P. & Schneider, J. (1999). Astron. Astrophy. Suppl. 134, 553.Google Scholar
Sasaki, T., Stewart, G.R. & Ida, S. (2010). Astrophy. J. 714, 1052.Google Scholar
Scharf, C.A. (2006). Astrophy. J. 648, 1196.CrossRefGoogle Scholar
Segatz, M., Spohn, T., Ross, M.N. & Schubert, G. (1988). Icarus 75, 187.CrossRefGoogle Scholar
Selsis, F. et al. (2007). Astron. Astrophy. 476, 1373.Google Scholar
Simon, A., Szatmáry, K. & Szabó, G.M. (2007). Astron. Astrophy. 470, 727.Google Scholar
Sohl, F., Sears, W.D. & Lorenz, R.D. (1995). Icarus 115, 278.Google Scholar
Sotin, C. et al. (2005). Nature 435, 786.CrossRefGoogle Scholar
Spencer, J.R. et al. (2000). Science 288, 1198.Google Scholar
Spencer, J.R. et al. (2006). Science 311, 1401.Google Scholar
Szabó, G.M., Szatmáry, K., Divéki, Z. & Simon, A. (2006). Astron. Astrophy. 450, 395.Google Scholar
Tobie, G., Čadek, O. & Sotin, C. (2008). Icarus 196, 642.Google Scholar
Tusnski, L.R.M. & Valio, A. (2011). Astrophy. J. 743, 97.Google Scholar
Williams, D.M., Kasting, J.F. & Wade, R.A. (1997). Nature 385, 234.CrossRefGoogle Scholar
Yang, J., Cowan, N.B. & Abbot, D.S. (2013). Astrophy. J. 771, L45.Google Scholar
Zahn, J.-P. (1977). Astron. Astrophy. 57, 383.Google Scholar