Long Propagation Periods of Residuals in the Motion of a Comet

Abstract

P/Halley In a previous paper (Kiang 1973), I derived a differential equation which governs the behaviour of the residual O - C in the time of perihelion passage of a comet. The work was stimulated by the discovery (Brady 1972) that a long periodicity of about 600 years seemed to be present in the residual for P/Halley. The derivation was based on the following assumptions: 1.The system consists of only the Sun, Jupiter and P/Halley, and Jupiter is assumed to move in a circular orbit with a period P′ = 11.8614 yr.2.P/Halley is assumed to move in a fixed Keplerian orbit with a period P = (13/2) P′ exactly, so that the whole system is strictly recurrent with a period Po = 13 P′ = 154.198 yr.