CORRECTIONS AND NEW DEVELOPMENTS IN RIGID-EARTH NUTATION THEORY. II. INFLUENCE OF SECOND-ORDER GEOPOTENTIAL AND DIRECT PLANETARY EFFECT

In a recent paper, Souchay & Kinoshita (1996) re- calculatedthecoefcientsofthenutationforarigid-Earthmodel due to the main luni-solar potential (coming from J2), with re- spect to the values given by Kinoshita & Souchay (1990), by taking into account an updated value of the general precession in longitude. In the following we complete this study by com- puting the coefcients coming from the lunar influence on the second-order geopotential (J3, C2;2, S2;2, J4) and those coming from the direct torque exerted by the planets. We notice some corrections to be done with respect to the tables of Kinoshita & Souchay(1990), and we show that the agreement with com- putations done by Hartmann et al. (1995) for the J3 part and Williams (1995) for the direct planetary effect is remarkable, although the way of calculation is quite different.