Exoplanets & Exomoons

Rocky Planets in the Habitable Zone of Tight Binary Stars with a Known Gas Giant

By Keith Cowing
May 26, 2015
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Rocky Planets in the Habitable Zone of Tight Binary Stars with a Known Gas Giant

Locating planets in HabitableZones (HZs) around other stars is a growing field in contemporary astronomy.

Since a large percentage of all G-M stars in the solar neighbourhood are expected to be part of binary or multiple stellar systems, investigations of whether habitable planets are likely to be discovered in such environments are of prime interest to the scientific community.

As current exoplanet statistics predicts that the chances are higher to find new worlds in systems that are already known to have planets, we examine four known extrasolar planetary systems in tight binaries in order to determine their capacity to host additional habitable terrestrial planets. Those systems are Gliese 86, gamma Cephei, HD 41004 and HD 196885. In the case of gamma Cephei, our results suggest that only the M dwarf companion could host additional potentially habitable worlds.

Neither could we identify stable, potentially habitable regions around HD 196885 A. HD 196885 B can be considered a slightly more promising target in the search for Earth-twins. Gliese 86 A turned out to be a very good candidate, assuming that the systems history has not been excessively violent. For HD 41004, we have identified admissible stable orbits for habitable planets, but those strongly depend on the parameters of the system.

A more detailed investigation shows that for some initial conditions stable planetary motion is possible in the HZ of HD 41004 A. In spite of the massive companion HD 41004 Bb, we found that HD 41004 B, too, could host additional habitable worlds.

Can there be additional rocky planets in the Habitable Zone of tight binary stars with a known gas giant?

Barbara Funk, Elke Pilat-Lohinger, Siegfried Eggl
(Submitted on 26 May 2015)
Comments: 9 pages
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Journal reference: Monthly Notices of the Royal Astronomical Society, Volume 448, Issue 4, p.3797-3805, 2015
DOI: 10.1093/mnras/stv253
Cite as: arXiv:1505.07069 [astro-ph.EP] (or arXiv:1505.07069v1 [astro-ph.EP] for this version)
Submission history
From: Barbara Funk
[v1] Tue, 26 May 2015 18:07:59 GMT (348kb)

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻