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arXiv · 0712.3219

Habitability of Super-Earths: Gliese 581c and 581d

W. von Bloh·C. Bounama·M. Cuntz·S. Franck
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Abstract

The unexpected diversity of exoplanets includes a growing number of super-Earth planets, i.e., exoplanets with masses smaller than 10 Earth masses. Unlike the larger exoplanets previously found, these smaller planets are more likely to have a similar chemical and mineralogical composition to the Earth. We present a thermal evolution model for super-Earth planets to identify the sources and sinks of atmospheric carbon dioxide. The photosynthesis-sustaining habitable zone (pHZ) is determined by the limits of biological productivity on the planetary surface. We apply our model to calculate the habitability of the two super-Earths in the Gliese 581 system. The super-Earth Gl 581c is clearly outside the pHZ, while Gl 581d is at the outer edge of the pHZ. Therefore it could at least harbor some primitive forms of life.

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W. von Bloh, C. Bounama, M. Cuntz, S. Franck. 2008-02-19. Habitability of Super-Earths: Gliese 581c and 581d. https://doi.org/10.1017/s1743921308017031

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