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Why do we find ourselves around a yellow star instead of a red star?

  • Jacob Haqq-Misra (a1) (a2), Ravi Kumar Kopparapu (a1) (a2) (a3) (a4) and Eric T. Wolf (a5)
Abstract
Abstract

M-dwarf stars are more abundant than G-dwarf stars, so our position as observers on a planet orbiting a G-dwarf raises questions about the suitability of other stellar types for supporting life. If we consider ourselves as typical, in the anthropic sense that our environment is probably a typical one for conscious observers, then we are led to the conclusion that planets orbiting in the habitable zone of G-dwarf stars should be the best place for conscious life to develop. But such a conclusion neglects the possibility that K-dwarfs or M-dwarfs could provide more numerous sites for life to develop, both now and in the future. In this paper we analyse this problem through Bayesian inference to demonstrate that our occurrence around a G-dwarf might be a slight statistical anomaly, but only the sort of chance event that we expect to occur regularly. Even if M-dwarfs provide more numerous habitable planets today and in the future, we still expect mid G- to early K-dwarfs stars to be the most likely place for observers like ourselves. This suggests that observers with similar cognitive capabilities as us are most likely to be found at the present time and place, rather than in the future or around much smaller stars.

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Corresponding author
e-mail: jacob@bmsis.org
References
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Abe Y., Abe-Ouchi A., Sleep N.H. & Zahnle K.J. (2011). Habitable zone limits for dry planets. Astrobiology 11, 443460.
Anglada-Escudé G. et al. (2016). A terrestrial planet candidate in a temperate orbit around Proxima Centauri. Nature 536, 437440.
Bostrom N. (1999). The doomsday argument is alive and kicking. Mind 108, 539551.
Bostrom N. (2002). Anthropic Bias: Observation Selection Effects in Science and Philosophy. Routledge, New York, NY.
Bostrom N. & Ćirković M.M. (2003). The doomsday argument and the self-indication assumption: reply to Olum. Philos. Quart. 53, 8391.
Carone L., Keppens R. & Decin L. (2014). Connecting the dots: a versatile model for the atmospheres of tidally locked Super-Earths. Monthly Notices Royal Astron. Soc. 445, 930945.
Carter B. (1974). Large number coincidences and the anthropic principle in cosmology. In Confrontation of Cosmological Theories with Observational Data, ed. Longair M.S., pp. 291298. Springer, Netherlands.
Carter B. & McCrea W.H. (1983). The anthropic principle and its implications for biological evolution [and discussion]. Philos. Trans. Royal Soc. Lond. A: Math. Phys. Eng. Sci. 310, 347363.
Cuntz M. & Guinan E.F. (2016). About exobiology: the case for dwarf K stars. Astrophys. J. 827, 79.
DeVito C.L. (2011). On the universality of human mathematics. In Communication with Extraterrestrial Intelligence, ed. Vakoch D.A., pp. 439448. Albany, NY.
Dole S.H. (1964). Habitable Planets for Man. Blaisedell, New York.
Dressing C.D. & Charbonneau D. (2015). The occurrence of potentially habitable planets orbiting M dwarfs estimated from the full Kepler dataset and an empirical measurement of the detection sensitivity. Astrophys. J. 807, 45.
Edson A., Lee S., Bannon P., Kasting J.F. & Pollard D. (2011). Atmospheric circulations of terrestrial planets orbiting low-mass stars. Icarus 212, 113.
Edson A.R., Kasting J.F., Pollard D., Lee S. & Bannon P.R. (2012). The carbonate-silicate cycle and CO2/climate feedbacks on tidally locked terrestrial planets. Astrobiology 12, 562571.
Foreman-Mackey D., Hogg D.W. & Morton T.D. (2014). Exoplanet population inference and the abundance of Earth analogs from noisy, incomplete catalogs. Astrophys. J. 795, 64.
Gillon M. et al. (2017). Seven temperate terrestrial planets around the nearby ultracool dwarf star TRAPPIST-1. Nature 542, 456460.
Gott J.R. (1993). Implications of the Copernican principle for our future prospects. Nature 363, 315319.
Grinspoon D. (2009). Lonely Planets. Harper Collins, New York, NY.
Haberle R.M., McKay C.P., Tyler D. & Reynolds R.T. (1996). Can synchronously rotating planets support an atmosphere? In Circumstellar Habitable Zones, ed. Doyle L.R. Travis House, Menlo Park, CA.
Haqq-Misra J., Kopparapu R.K., Batalha N.E., Harman C.E. & Kasting J.F. (2016). Limit cycles can reduce the width of the habitable zone. Astrophys. J. 827, 120.
Haussler D. (2016). Odds for an enlightened rather than barren future. arXiv preprint arXiv:1608.05776.
Heller R. (2012). Exomoon habitability constrained by energy flux and orbital stability. Astron. Astrophys. 545, L8.
Heller R. & Barnes R. (2013). Exomoon habitability constrained by illumination and tidal heating. Astrobiology 13, 1846.
Joshi M. (2003). Climate model studies of synchronously rotating planets. Astrobiology 3, 415427.
Joshi M., Haberle R.M. & Reynolds R.T. (1997). Simulations of the atmospheres of synchronously rotating terrestrial planets orbiting M dwarfs: conditions for atmospheric collapse and the implications for habitability. Icarus 129, 450465.
Kopparapu R.K. & Barnes R. (2010). Stability analysis of single-planet systems and their habitable zones. Astrophys. J. 716, 1336.
Kopparapu R.K., Ramirez R., Kasting J.F., Eymet V., Robinson T.D., Mahadevan S., Terrien R.C., Domagal-Goldman S., Meadows V. & Deshpande R. (2013). Habitable zones around main-sequence stars: new estimates. Astrophys. J. 765, 131.
Kopparapu R.K., Ramirez R.M., SchottelKotte J., Kasting J.F., Domagal-Goldman S. & Eymet V. (2014). Habitable zones around main-sequence stars: dependence on planetary mass. Astrophys. J. 787, L29.
Kopparapu R.K., Wolf E.T., Haqq-Misra J., Yang J., Kasting J.F., Meadows V.S., Terrien R. & Mahadevan S. (2016). The inner edge of the habitable zone for synchronously rotating planets around low-mass stars using general circulation models. Astrophys. J. 819, 84.
Korb K.B. & Oliver J.J. (1998). A refutation of the doomsday argument. Mind 107, 403410.
Kurzweil R. (2005). The Singularity is Near: When Humans Transcend Biology. Penguin, New York, NY.
Leconte J., Forget F., Charnay B., Wordsworth R., Selsis F., Millour E. & Spiga A. (2013). 3D climate modeling of close-in land planets: circulation patterns, climate moist bistability, and habitability. Astron. Astrophys. 554, A69.
Lissauer J.J. (2007). Planets formed in habitable zones of M dwarf stars probably are deficient in volatiles. Astrophys. J. Lett. 660, L149.
Loeb A., Batista R.A. & Sloan D. (2016). Relative likelihood for life as a function of cosmic time. J. Cosmol. Astropart. Phys. 2016, 040.
Luger R. & Barnes R. (2015). Extreme water loss and abiotic O2 buildup on planets throughout the habitable zones of M dwarfs. Astrobiology 15, 119143.
Merlis T.M. & Schneider T. (2010). Atmospheric dynamics of Earth-like tidally locked aquaplanets. J. Adv. Model. Earth Syst. 2, 13.
Monton B. (2003). The doomsday argument without knowledge of birth rank. Philos. Quart. 53, 7982.
Olum K.D. (2002). The doomsday argument and the number of possible observers. Philos. Quart. 52, 164184.
Petigura E.A., Howard A.W. & Marcy G.W. (2013). Prevalence of Earth-size planets orbiting Sun-like stars. Proc. Natl. Acad. Sci. USA 110, 1927319278.
Ramirez R.M. & Kaltenegger L. (2014). The habitable zones of pre-main-sequence stars. Astrophys. J. Lett. 797, L25.
Raymond S.N., Barnes R., Veras D., Armitage P.J., Gorelick N. & Greenberg R. (2009). Planet-planet scattering leads to tightly packed planetary systems. Astrophys. J. Lett. 696, L98.
Segura A., Walkowicz L.M., Meadows V., Kasting J. & Hawley S. (2010). The effect of a strong stellar flare on the atmospheric chemistry of an Earth-like planet orbiting an M dwarf. Astrobiology 10, 751771.
Silburt A., Gaidos E. & Wu Y. (2015). A statistical reconstruction of the planet population around Kepler solar-type stars. Astrophys. J. 799, 180.
Standish R. (2013). Ants are not conscious. Open J. Philos. 3, 14.
Tarter J.C. et al. (2007). A reappraisal of the habitability of planets around M dwarf stars. Astrobiology 7, 30–65.
Tian F. & Ida S. (2015). Water contents of Earth-mass planets around M dwarfs. Nature Geosci. 8, 177–180.
Wolf E.T. & Toon O.B. (2015). The evolution of habitable climates under the brightening sun. J. Geophys. Res. Atmos. 120, 57755794.
Yang J., Cowan N.B. & Abbot D.S. (2013). Stabilizing cloud feedback dramatically expands the habitable zone of tidally locked planets. Astrophys. J. Lett. 771, L45.
Yang J., Boué G., Fabrycky D.C. & Abbot D.S. (2014). Strong dependence of the inner edge of the habitable zone on planetary rotation rate. Astrophys. J. Lett. 787, L2.
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International Journal of Astrobiology
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