Planets in habitable zones: A study of the binary Gamma Cephei
- Author(s)
- Rudolf Dvorak, Elke Pilat-Lohinger, Barbara Funk, Florian Freistetter
- Abstract
The recently discovered planetary system in the binary ? Cep was studied concerning its dynamical evolution. We confirm that the orbital parameters found by the observers are in a stable configuration. The primary aim of this study was to find stable planetary orbits in a habitable region in this system, which consists of a double star (a = 21.36 AU) and a relatively close (a = 2.15 AU) massive (1.7 mjup sin i) planet. We did straightforward numerical integrations of the equations of motion in different dynamical models and determined the stability regions for a fictitious massless planet in the interval of the semimajor axis 0.5 AU <a <1.85 AU around the more massive primary. To confirm the results we used the Fast Lyapunov Indicators (FLI) in separate computations, which are a common tool for determining the chaoticity of an orbit. Both results are in good agreement and unveiled a small island of stable motions close to 1 AU up to an inclination of about 15° (which corresponds to the 3:1 mean motion resonance between the two planets). Additionally we computed the orbits of earthlike planets (up to 90 earthmasses) in the small stable island and found out, that there exists a small window of stable orbits on the inner edge of the habitable zone in ? Cep even for massive planets.
- Organisation(s)
- Department of Astrophysics
- External organisation(s)
- Friedrich-Schiller-Universität Jena
- Journal
- Astronomy & Astrophysics
- Volume
- 398
- ISSN
- 0004-6361
- Publication date
- 2003
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103003 Astronomy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/95eb7f90-2130-452c-a0e5-0328d591d0d6