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.