The libration of the saturnian satellite dione B

Previously published positions of Dione B are combined with new observations reported in this paper to determine the motion. The data are fit to the analytic solution of Erdi (1978) to derive the parameters of the libratory motion. The satellite oscillates about the leading equilateral libration point (L₄) of Dione with a period of 785.0±0.5 days. The maximum sepaparation in orbital longitude from Dione of 76.7° was reached on UT 1980 April 20.3±1 days; the minimum separation is 46.7°.