Geodynamics of terrestrial exoplanets

Artistic sketch of Kepler-22b, a recently discovered exoplanet with comparable mass (within 10 Earth masses) of the planet Earth.

The discovery of extrasolar Earth-sized planets has encouraged research into their potential for habitability. One of the generally agreed[1] requirements for a life-sustaining planet is a mobile, fractured lithosphere cyclically recycled into a vigorously convecting mantle, in a process commonly known as plate tectonics. Plate tectonics provide a means of geochemical regulation of atmospheric particulates, as well as removal of carbon from the atmosphere. This prevents a “runaway greenhouse” effect that can result in inhospitable surface temperatures and vaporization of liquid surface water.[2] Planetary scientists have not reached a consensus on whether Earth-like exoplanets have plate tectonics, but it is widely thought that the likelihood of plate tectonics on an Earth-like exoplanet is a function of planetary radius, initial temperature upon coalescence, insolation, and presence or absence of liquid-phase surface water.[3][4][5][6]

  1. ^ Cite error: The named reference Noack_Breuer_2014 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference Kaltenegger_Sasselov_2010 was invoked but never defined (see the help page).
  3. ^ O'Neill, C.; Lenardic, A. (11 October 2007). "Geological consequences of super-sized Earths". Geophysical Research Letters. 34 (19): L19204. Bibcode:2007GeoRL..3419204O. doi:10.1029/2007GL030598.
  4. ^ Valencia, D.; O'Connell, R.J.; Sasselov, D. (20 November 2007). "Inevitability of Plate Tectonics on Super-Earths". The Astrophysical Journal. 670 (1): 45–48. arXiv:0710.0699. Bibcode:2007ApJ...670L..45V. doi:10.1086/524012.
  5. ^ Van Summeren, J.; Conrad, C.P.; Gaidos, E. (20 July 2011). "Mantle convection, plate tectonics, and volcanism on hot exo-earths". The Astrophysical Journal Letters. 736 (1): L15. arXiv:1106.4341. Bibcode:2011ApJ...736L..15V. doi:10.1088/2041-8205/736/1/L15.
  6. ^ Korenaga, J. (10 December 2010). "On the Likelihood of Plate Tectonics on Super-Earths: Does Size Matter?". The Astrophysical Journal Letters. 725 (1): 43–46. Bibcode:2010ApJ...725L..43K. doi:10.1088/2041-8205/725/1/L43.