On the Habitability of Planets in Binary Star Systems

Author(s)

E. Pilat-Lohinger, S. Eggl, M. Gyergyovits

Abstract

The discovery of more and more extra-solar planets in and around binary

star systems cause questions concerning the determination of the

classical habitable zone (HZ). We present calculations of the radiative

and gravitational perturbations of two stars on a terrestrial planet

moving in the HZ in different binary - planet configurations. Two

types of planetary motion will be considered, i.e. S-type motion (or

circumprimary motion) where the planet orbits one star only and P-type

(or circumbinary motion) where the binary revolves inside the planet's

orbit. It was found that the HZ in S-type configurations tend to be

gravitationally dominated, the radiative input due to the second star is

negligible compared to its dynamical influence causing secular changes

in the eccentricity of the planets. This alters the amount of incident

radiation significantly. In P-type configurations the radiation

estimates can be determined on shorter time-scales. The radiation

amplitude depends on the eccentricity of the binary in both

configurations. Finally we present time independent analytical estimates

about the habitability of a terrestrial planet in the HZ of a binary

star system as shown by Eggl et al.(2012). This work was financed by

the Austrian Science Fonds (FWF) P22603-N16 and AS11608-N16 and S.Eggl

was financed by the University of Vienna (Forschungsstipendium 2012).

Ref.: Eggl, S., Pilat-Lohinger, E., Gerogakarakos, N., Gyergyovits, M.

and Funk, B., "Habitable Zones in S-Type Binary Star Systems", ApJ,

submitted.

Organisation(s)

Department of Astrophysics

Journal

Geophysical Research Abstracts

Volume

14

Pages

12406

ISSN

1029-7006

Publication date

04-2012

Austrian Fields of Science 2012

103004 Astrophysics, 103003 Astronomy

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