TITLE:
The Physics of Rotational Flattening and the Point Core Model
AUTHORS:
Hanno Essén
KEYWORDS:
Rotation, Angular Velocity, Oblateness, Flattening, Figure of Celestial Body, Gravitational Quadrupole, Point Core Model, Moment of Inertia
JOURNAL NAME:
International Journal of Geosciences,
Vol.5 No.6,
May
6,
2014
ABSTRACT: The
effect of rotation on the shape (figure) and gravitational quadrupole of
astronomical bodies is calculated by using an approximate point core model: A
point mass at the center of an ellipsoidal homogeneous fluid. Maclaurin’s
analytical result for homogenous bodies generalizes to this model and leads to
very accurate analytical results connecting the three observables: oblateness (ò),
gravitational quadrupole (J2), and angular velocity parameter (q). The
analytical results are compared to observational data for the planets and a good
agreement is found. Oscillations near equilibrium are studied within the model.