The role of dynamics on the habitability of an Earth-like planet

Author(s)
Elke Pilat-Lohinger
Abstract

From the numerous detected planets outside the Solar System, no terrestrial planet comparable with our Earth has been discovered so far. The search for an Exo-Earth is certainly a big challenge which may require the detections of planetary systems resembling our Solar System in order to find life like on Earth. However, even if we find Solar System analogues, it is not certain that a planet in Earth position will have similar circumstances as those of the Earth. Small changes in the architecture of the giant planets can lead to orbital perturbations which may change the conditions of habitability for a terrestrial planet in the habitable zone (HZ). We present a numerical investigation where we first study the motion of test-planets in a particular Jupiter-Saturn configuration for which we can expect strong gravitational perturbations on the motion at the Earth's position according to a previous work. In this study, we show that these strong perturbations can be reduced significantly by the neighbouring planets of Earth. In the second part of our study, we investigate the motion of test-planets in inclined Jupiter-Saturn systems where we analyse changes in the dynamical behaviour of the inner planetary system. Moderate values of inclination seem to counteract the perturbations in the HZ, while high inclinations induce more chaos in this region. Finally, we carry out a stability study of the actual orbits of Venus, Earth and Mars moving in the inclined Jupiter-Saturn systems for which we used the Solar System parameters. This study shows that the three terrestrial planets will only move in low-eccentric orbits if Saturn's inclination is <=10°. Therefore, it seems that it is advantageous for the habitability of Earth when all planets move nearly in the same plane.

Organisation(s)
Department of Astrophysics
Journal
International Journal of Astrobiology
Volume
14
Pages
145 - 152
No. of pages
8
ISSN
1473-5504
DOI
https://doi.org/10.1017/S1473550414000469
Publication date
04-2015
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics
Keywords
ASJC Scopus subject areas
Ecology, Evolution, Behavior and Systematics, Space and Planetary Science, Earth and Planetary Sciences (miscellaneous), Physics and Astronomy (miscellaneous)
Portal url
https://ucrisportal.univie.ac.at/en/publications/the-role-of-dynamics-on-the-habitability-of-an-earthlike-planet(3106d299-70b2-4bf0-9337-593f9ddcdfde).html