In ogni Osservatorio che si rispetti, occorre.....OSSERVARE,fatelo anche voi !http://www.youtube.com/watch?v=Xv3i_xxcIdkhttp://www.youtube.com/watch?v=qdJHUSAwU_Yhttp://www.youtube.com/watch?v=msaqC-5VF-Q&feature=related http://www.youtube.com/watch?v=BDtZQj0Dlp0http://www.youtube.com/watch?v=w9UM7rbrQtw