Concerning the “D” Ring of Saturn

Abstract

IN his excellent chronological review book of observations, The Planet Saturn, Alexander1 compares the outer, “D” ring of Saturn to the Loch Ness Monster: some see it, and some do not. During the second half of the nineteenth century a number of visual observations were reported by experienced observers but the issue seems to have been settled by Barnard2 in 1909, using the 40 in. Yerkes refractor visually and getting negative results. Apparently few, if any, attempts have been made photographically to detect a ring outside the well known A, B and C rings.