Abstract. In this paper, we publish 1206 measurements of positions of the major satellites of Saturn made in 1990Saturn made in , 1991Saturn made in , 1993Saturn made in and 1994 using CCD detectors attached to the 1-metre Jacobus Kapteyn Telescope on the island of La Palma. Analysis of the data as inter-satellite positions shows that the observations of Tethys, Dione, Rhea and Titan have root-mean-square residuals of 0. 08, corresponding to 500 km at the distance of Saturn.

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The stability of the new horizontal axis Levitron is compared with that of the vertical axis device. The rotation frequency ranges are similar because they are determined by the same precessional micro-trap, for which some theory is given. But the macro-trap of the horizontal axis system gives it far greater mechanical stability. Field-line studies allow this to be more easily visualized. The greater stability allows for educational experiments which could only be contemplated with the old Levitron: driven precession and nutation and motion along the field lines. These experiments illustrate some very fundamental space dynamics and several other topics. The enhanced stability may also lead to electro-mechanical applications.

Abstract. In this paper, we publish measurements of 1514 positions of the major satellites of Saturn made in 1995 and 1997 using CCD detectors attached to the 1-metre Jacobus Kapteyn Telescope on the island of La Palma. Analysis of the data as inter-satellite positions shows that the observations of Tethys, Dione, Rhea and Titan have root-mean-square residuals of 0. 08 in 1995 and 0. 10 in 1997.

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