EXTENDED SCHUBART AVERAGING

The purpose of this paper is the presentation of an integrator for the average motion of an asteroid in mean motion commensurability with Ju piter. The program is valid for any (p + q)/p mean motion commensurabi lity (except when q = 0) and uses a double precision version of DE (Sh ampine and Gordon 1975) as propagator. The averaged equations of motio n of the asteroid are evaluated in a non-singular way for any value of the eccentricities and the inclinations and the orbit of Jupiter is d escribed by the most important terms in Longstop 1B (Nobili et al. 198 9). This integrator can be considered as an extension of the well know n Schubart Averaging (Schubart 1978) in which Jupiter is moving on a f ixed ellipse.