Roche Coordinates

Abstract

The preceding chapter of this monograph has been concerned primarily with the geometry of the Roche equipotential surfaces surrounding a gravitational dipole of two finite masses in Keplerian orbit. This geometry finds many applications to the phenomena exhibited by close binary systems—in particular, to an interpretation of photometric (and spectroscopic) observations of pairs whose components happen to eclipse each other in the course of their orbital cycle—phenomena to which we shall devote specific attention in the last part of this book. But it is not only to an analysis of descriptive observations that the subject matter of the last chapter can provide an appropriate basis. Much more important in this connection are the phenomena concerned with the stability (both vibrational and secular) of the components of close binary systems (and of their interaction) and gas streams which may revolve between them, that must be approached on the hydrodynamical basis, and in which the shape of the components is bound to play a crucial role.