Its possible that 1y1 denoted planet, wyw is without atmosphere, and zyz is with atmosphere. The medium (earth sized?) and large (gas giant?) planets would have atmosphere, a little planet wouldn't. We will have to wait for more information to resolve this controversy. I do like W as a naming convention for the planets. In reply to some of the recent postings, I think the pP...Pp as picture interpretation is obsolete. The following pictures could just be meant to explain the p is radius or circle. Of course no one knows what the lone p means. Look at Andrew Plotkin's WWW page to see how the multiple G's make paragraphs.