Relation between rotation and lightcurve of 4179 Toutatis

This paper presents results of modelling light variations of a freely prece ssing asteroid, assuming its ellipsoidal shape and a geometric light scatte ring law. The method is based on numerical integration of Euler equations, combined with the explicit expression of an asteroid's brightness as a func tion of Euler angles. Modelling is applied to simulate the lightcurve of 41 79 Toutatis according to its triaxial ellipsoid shape and spin state given by Hudson & Ostro (1995). A good agreement is obtained between the frequenc ies of the simulated and observed lightcurves, The results explain some app arent discrepancies between the periods obtained from photometric and radar observations.