5 Conclusion

Ephemerides for the physical observations of (216) Kleopatra have been constructed. They provide, at any given epoch of observation, the aspect and orientation in the plane-of-sky view of this object as well as its brightness distribution. The present paper shows that the radar-derived nominal-model of Kleopatra could be improved to be fully compatible with the whole set of available data for this object, including photometric lightcurves, stellar occultation data, and high resolution interferometric data from the HST/FGS. It results from this analysis that the available data coming from different observational techniques suggest that the actual shape of Kleopatra is more elongated than the radar nominal-solution. On the other hand, models with an empty gap and/or "overlapping ellipsoids'' cannot be totally ruled out on the basis of current observational evidence. A more detailed assessment of this possibility deserves some further scrutiny, due to potential implications for our understanding on the formation and evolution of this object in particular, and of binary asteroids in general. A combined analysis of existing and future high-resolution observations from the HST/FGS interferometer, or from the ESO/VLT in the optical domain and/or radar data that will be hopefully obtained in the future, should lead to a more conclusive evidence about the real shape and overall structure of this interesting object. This should be a necessary starting point for a more detailed modelling of the internal structure of Kleopatra, and its overall collisional history.