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Detection of arcs in Saturn's F ring during the 1995 Sun ring-plane crossing

S. Charnoz·A. Brahic·C. Ferrari·I. Grenier·F. Roddier·P. Thebault
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Abstract

Observations of the November 1995 Sun crossing of the Saturn's ring-plane made with the 3.6m CFH telescope, using the UHAO adaptive optics system, are presented here. We report the detection of four arcs located in the vicinity of the F ring. They can be seen one day later in HST images. The combination of both data sets gives accurate determinations of their orbits. Semi-major axes range from 140020 km to 140080 km, with a mean of 140060 +- 60 km. This is about 150 km smaller than previous estimates of the F ring radius from Voyager 1 and 2 data, but close to the orbit of another arc observed at the same epoch in HST images.

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S. Charnoz, A. Brahic, C. Ferrari, I. Grenier, F. Roddier, P. Thebault. 2000-10-23. Detection of arcs in Saturn's F ring during the 1995 Sun ring-plane crossing. https://doi.org/10.1051/0004-6361%3A20000183

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