OBSERVATIONS OF SATURN'S FAINTER SATELLITES DURING THE AUGUST 1995 RING-PLANE CROSSING

Poulet F.(1), Sicardy B.(1), Beuzit J.L.(2), Prado P.(3)

(1) Observatoire de Paris
(2) ESO Garching
(3) ESO La Silla

During a 6 night period spanning August 10, 1995 ring plane crossing, observations of Saturn's ring system have been obtained using the Adonis adaptive optics camera with a short K filter, at the 3.6-m telescope of the European Southern Observatory (ESO La Silla-Chile). The markedly reduced scattered light from the rings at this time allowed a study of the small satellites of the Saturn system. Besides Janus, Epimetheus and Pandora observed at their expected locations, two unresolved objects have been detected (IAUC 6269). These objects have been identified with the new moons 1995S5 and 1995S6, which have been detected on frames obtained with the Hubble Space Telescope (HST), more than one day later (IAUC 6243). The ESO data improve the orbital parameters of 1995S5 and bring it closer to the F ring. HST Observations during the November 1995 solar crossing (Nicholson et al. Science 272, 509) show several very elongated features apparently within the F ring, but there is no correlation between the extrapoled positions of 1995S5 and 1995S6 and those of the arcs seen in November. So, these new moons are probably not solid moons, but transient clumps of debris, or arcs, which are moderately opaque.