Orbital stability of hypothetical terrestrial planets in extrasolar
planetetary systems based on Jumping Jupiter model
Authors:
Makoto Obinata,
Tokyo institute of technology
Kasumi
Yamashiro, Tokyo institute of technology
Tatsuya Mitsui,
Tokyo U
Shigeru Ida,
Tokyo institute of technology
Abstract:
Orbital
stability of hypothetical terrestrial planets in extrasolar planetetary
systems with gas giant planets in eccentric orbits is investigated
through numerical integrations, based on Jumping Jupiter model. In the
model, giant planets originally in nearly circular orbits start orbital
crossing until one of the giants is ejected, leaving the others in
stable eccentric orbits. Orbital stability of hypothetical terrestrial
planets in the present orbital configurations of known extrasolar
planets has been investigated by many authors. However, the
perturbations from the giant planets during the orbit crossing can be
so strong. So, we have carried out orbital integrations of systems with
three gas giants and hypothetical (massless) terrestrial planets in
orbits inside the giants’ orbits to investigate the orbital stability
of the terrestrial planets during and after the orbit crossing. In the
regions relatively close to the giants’ orbits, terrestrial planets are
ejected through close approach to the giants, while in the innermost
region they are stable. However, we found that in a broad range of
intermediate semimajor axis in which their orbits are stable in the
configurations after the orbital crossing, they hit the host stars
although they keep far away from the giants during the orbit crossing.
We found that secular resonances that randomly move according to the
giants’ orbital change during the orbit crossing are responsible for
it. Since the perturbations are secular, the eccentricities are
monotonically increases, resulting in hitting the host star rather than
ejection