ASTEROID LIGHTCURVE OBSERVATIONS NEAR STATIONARY-POINTS - (4179) TOUTATIS IN 1997 FEBRUARY

Lightcurve observations of asteroids with long-spin periods (say, more than a few days) are particularly important regarding the detection o f a non-principal axis spin state. However, it is not easy for such ob servations to achieve photometric accuracy comparable to that for shor t-period spin asteroids, since slow-spin asteroids inevitably require long duration and coordinated observations and the use of different re ference stars during a run. We propose here the advantage of observati ons near stationary points for long-spin asteroids, where the same ref erence stars can be used throughout. This proposal was tested for CCD lightcurve observations of asteroid (4179) Toutatis, which were perfor med near its stationary point in 1997 February. From six night observa tions spanning 11 days, a spin period of 7.50+/-0.2 d was obtained usi ng two independent methods of period analysis; this value has been fou nd to be in fairly good agreement with the periods obtained by Hudson and Ostro(1995, AAA 64.098.037), and Spencer et al. (1995, AAA 64.098. 052).