Near-infrared magnitudes and effective temperatures from models have then been compared with observed values. Direct detection and astrometric observations have been used to solve the AB Dor C orbit and obtain a dynamical mass estimate. We report on the nature and orbits of bodies sighted in the F ring, two of which may have persisted for a year or more.ĪB Dor C, a low-mass companion to the young star AB Dor A has recently been imaged.

Orbital in-tegrations show that Methone is perturbed by Mimas, Pallene is perturbed by Enceladus, and Polydeuces librates around Dione's L5 point with a period of about 791 days. Orbital integrations involving Atlas yield a mass of GM Atlas ¼ (0:44 AE 0:04) 10 À3 km 3 s À2, 3 times larger than reported previously (GM is the product of the Newtonian constant of gravitation G and the satellite mass M). Atlas is significantly perturbed by Prometheus, and to a lesser extent by Pandora, through high-wavenumber mean-motion reso-nances. Refined orbits of Atlas, Prometheus, Pandora, Janus, and Epimetheus are based on Cassini, Voyager, Hubble Space Telescope, and Earth-based data and a numerical integration perturbed by all the massive satellites and each other. The orbit of the small satellite (S/2005 S1 ) discovered by Cassini in the Keeler gap in the outer A ring appears to be circular and coplanar no external perturbations are appar-ent. Using combined Cassini and Voyager observations, we obtain an eccentricity for Pan 7 times smaller than previously reported because of the predominance of higher quality Cassini data in the fit. The orbits presented here reflect improvements over our previously published values in that the time base of Cassini observations has been extended, and numerical orbital integrations have been performed in those cases in which simple precessing elliptical, inclined orbit solutions were found to be inadequate. We report on the orbits of the small, inner Saturnian satellites, either recovered or newly discovered in recent Cassini imaging observations.

Saturn moon atlas