A Widebinary Solar Companion as a Possible Origin of Sedna-like Objects
Abstract
Sedna is the first inner Oort cloud object to be discovered. Its dynamical origin remains unclear, and a possible mechanism is considered here. We investigate the parameter space of a hypothetical solar companion which could adiabatically detach the perihelion of a Neptune-dominated TNO with a Sedna-like semimajor axis. Demanding that the TNO’s maximum value of osculating perihelion exceed Sedna’s observed value of 76 AU, we find that the companion’s mass and orbital parameters (m c , a c , q c , Q c , i c ) are restricted to <Equation ID="Equa"> m_c>rapprox 5hskip.25emM_Jleft(Q_c/7850 AU q_c/7850 AUright)^{3/2} </Equation> during the epoch of strongest perturbations. The ecliptic inclination of the companion should be in the range 45{deg}lessapprox i_clessapprox 135{deg} if the TNO is to retain a small inclination while its perihelion is increased. We also consider the circumstances where the minimum value of osculating perihelion would pass the object to the dynamical dominance of Saturn and Jupiter, if allowed. It has previously been argued that an overpopulated band of outer Oort cloud comets with an anomalous distribution of orbital elements could be produced by a solar companion with present parameter values <Equation ID="Equb"> m_c≈ 5hskip.25emM_Jleft(9000 AU/a_cright)^{1/2}. </Equation> If the same hypothetical object is responsible for both observations, then it is likely recorded in the IRAS and possibly the 2MASS databases.
- Publication:
-
Earth Moon and Planets
- Pub Date:
- December 2005
- DOI:
- 10.1007/s11038-006-9078-6
- Bibcode:
- 2005EM&P...97..459M