Research Note

Simulating observable comets

II. Simultaneous stellar and galactic action

Astronomical Observatory of the A. Mickiewicz University, Słoneczna 36, 60-286 Poznań, Poland e-mail: dybol@amu.edu.pl

Received: 28 April 2005
Accepted: 22 June 2005

Abstract

This is the second in a series of papers presenting an attempt to reproduce the mechanisms acting currently on the Oort cloud of comets (Oort 1950, Bull. Astron. Inst. Nether., 11, 91) and producing the observed sample of long-period comets. We combine the effect of the close, recent stellar passage with the continuous action of the Galactic tidal perturbation, and concentrate on the dominant term of this effect, namely the tidal force induced by the galactic disk matter. The main results presented in the previous paper of this series are fully confirmed within a much more realistic model. The results we obtained is that the observable subpopulation of the Oort cometary cloud remained the same in number, even after the close stellar passage. The main output of such a passage is a short time variation in the observable influx of comets and strong asymmetries present in their perihelion direction distribution.