Reexamination of a photograph of Saturn taken on 15 November 1966 when the earth was nearly in the ring plane indicates that ring material does exist outside the visible rings, extending to more than 6 Saturnian radii. The observed brightness in blue light was estimated to be mB=19.5 ± 0.5 per linear arc second, implying a normal optical thickness, τ= 10-7 for ice-covered particles. For spacecraft passing through this region, the hazards are found to be minimal.
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