Specific Angular Momenta of Extrasolar Planetary Systems

Angular momentum in our solar system is distributed between the Sun's rotation and the planetary orbits, and largely resides in the orbital angular momentum of Jupiter. By treating the solar system as a two body central potential between the Sun and Jupiter, one can show that the orbital specific angular momentum of the two-body system exceeds the solar rotational specific angular momentum by nearly two orders of magnitude. We extend this analysis to the 210+ extrasolar planetary systems available in the Extrasolar Planet Encyclopedia and estimate the partitioning of each system's angular momentum into orbital and rotational components. We find the range of partitioning of specific angular momentum in these systems to be large, with some systems near the stellar rotational limit, and others with orbital specific angular momentum exceeding this limit by three orders of magnitude. We explore the implications of this partitioning both for solar system formation and in the light of undiscovered objects that might exist in those systems.