Survival of Terrestrial Planets in the Presence of Giant Planet Migration

The presence of "hot Jupiters," Jovian-mass planets with very short orbital periods orbiting nearby main-sequence stars, has been proposed to be primarily due to the orbital migration of planets formed in orbits initially much farther from the parent star. This migration affects the evolution of inner terrestrial planets in these systems. Previous analyses have assumed that no terrestrial planets survive after migration has occurred. We present numerical simulations showing that a significant fraction of terrestrial planets could survive the migration process and possibly return to near circular orbits relatively close to their original positions. A fraction of the final orbits are in the habitable zone, suggesting that planetary systems with close-in giant planets are viable targets for searches for Earth-like habitable planets around other stars.

[1]  Eric B. Ford,et al.  Dynamical Instabilities and the Formation of Extrasolar Planetary Systems , 1996, Science.

[2]  M. Mayor,et al.  A Jupiter-mass companion to a solar-type star , 1995, Nature.

[3]  P. Bodenheimer,et al.  Orbital migration of the planetary companion of 51 Pegasi to its present location , 1996, Nature.

[4]  S. Jacobsen How Old Is Planet Earth? , 2003, Science.

[5]  J. Kasting,et al.  Habitable zones around main sequence stars. , 1993, Icarus.

[6]  J. Chambers A hybrid symplectic integrator that permits close encounters between massive bodies , 1999 .

[7]  George W. Wetherill,et al.  Accumulation of a swarm of small planetesimals , 1989 .

[8]  Hansen,et al.  Migrating planets , 1998, Science.

[9]  Jack J. Lissauer,et al.  Formation of the Giant Planets by Concurrent Accretion of Solids and Gas , 1995 .

[10]  Kristen Menou,et al.  Dynamical habitability of known extrasolar planetary systems , 2003 .

[11]  K. Mezger,et al.  Rapid accretion and early core formation on asteroids and the terrestrial planets from Hf–W chronometry , 2002, Nature.

[12]  C. Agnor,et al.  Damping of Terrestrial-Planet Eccentricities by Density-Wave Interactions with a Remnant Gas Disk , 2002 .

[13]  Brett Gladman,et al.  Dynamics of Systems of Two Close Planets , 1993 .

[14]  M. Kuchner Volatile-rich Earth-Mass Planets in the Habitable Zone , 2003, astro-ph/0303186.

[15]  David E. Trilling,et al.  Easy Come, Easy Go: Orbital Migration and the Frequency of Giant Planet Formation , 2000 .

[16]  D. Davis,et al.  Accretional Evolution of a Planetesimal Swarm , 1997 .

[17]  W. Ward Protoplanet Migration by Nebula Tides , 1997 .

[18]  Philip J. Armitage,et al.  A Reduced Efficiency of Terrestrial Planet Formation following Giant Planet Migration , 2002, astro-ph/0211488.

[19]  F. Albarède,et al.  A short timescale for terrestrial planet formation from Hf–W chronometry of meteorites , 2002, Nature.

[20]  Hans Scholl,et al.  Terrestrial planet formation in exoplanetary systems with a giant planet on an external orbit , 2002 .

[21]  T. Quinn,et al.  Formation of Giant Planets by Fragmentation of Protoplanetary Disks , 2002, Science.

[22]  Francesco Marzari,et al.  Gravitational scattering as a possible origin for giant planets at small stellar distances , 1996, Nature.

[23]  S. Inaba,et al.  Runaway Growth of Planetary Embryos Facilitated by Massive Bodies in a Protoplanetary Disk , 2001, Science.

[24]  D. Lin,et al.  On the tidal interaction between protoplanets and the protoplanetary disk. III. Orbital migration of protoplanets , 1986 .

[25]  Harold F. Levison,et al.  THE FORMATION OF URANUS AND NEPTUNE AMONG JUPITER AND SATURN , 2001, astro-ph/0111290.

[26]  A. Boss Formation of Planetary-Mass Objects by Protostellar Collapse and Fragmentation , 2001 .

[27]  J. Chambers Making More Terrestrial Planets , 2001 .