Indexing Exoplanets with Physical Conditions Potentially Suitable for Rock-Dependent Extremophiles

Scatter plot of surface RSI versus interior RSI. The solid line marked for Mars is the threshold value for potentially habitable planets.

The search for different life forms elsewhere in the universe is a fascinating area of research in astrophysics and astrobiology. Currently, according to the NASA Exoplanet Archive database, 3876 exoplanets have been discovered.

The Earth Similarity Index (ESI) is defined as the geometric mean of radius, density, escape velocity, and surface temperature and ranges from 0 (dissimilar to Earth) to 1 (similar to Earth). The ESI was created to index exoplanets on the basis of their similarity to Earth. In this paper, we examined rocky exoplanets whose physical conditions are potentially suitable for the survival of rock-dependent extremophiles, such as the cyanobacteria Chroococcidiopsis and the lichen Acarospora.

The Rock Similarity Index (RSI) is first introduced and then applied to 1659 rocky exoplanets. The RSI represents a measure for Earth-like planets on which physical conditions are potentially suitable for rocky extremophiles that can survive in Earth-like extreme habitats (i.e., hot deserts and cold, frozen lands).

Madhu Kashyap Jagadeesh, Sagarika Rao Valluri, Vani Kari, Katarzyna Kubska, Łukasz Kaczmarek
(Submitted on 28 Feb 2020)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Journal reference: LIFE, 2020
DOI: 10.3390/life10020010
Cite as: arXiv:2002.12650 [astro-ph.EP] (or arXiv:2002.12650v1 [astro-ph.EP] for this version)
Submission history
From: Madhu Kashyap Jagadeesh
[v1] Fri, 28 Feb 2020 11:03:38 UTC (457 KB)

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