We have active collaborations with the Observatoire de la Côte d’Azur (Nice, France) (P. Michel, P. Tanga), the Dept. of Astronomy of the University of Maryland (USA) (D.C. Richardson), the Southwest Research Institute (Boulde, CO, USA) (D.D. Durda; W.F. Bottke), the Dept. de Física (Univ. de la República, Uruguay), the Instituto de Astrofísica de Andalucía (Tenerife, Spain), (J. Licandro; J. de León), the Instituto de Astrofísica de Andalucía (Granada, Spain), the Institut d’ Estudis Espacials de Catalunya (CSIC)(Barcelona, Spain) (J.M. Trigo).