On the evening of Saturday, 5 September, 1998, I again attended the full-Moon non-star party that one of the local bunch of observers throws regularly, and again took advantage of clear sky and a pleasant back yard to observe the full Moon naked-eye. A little light from other houses and the street helped contract my pupil somewhat, increasing my visual acuity, and I was seated motionlessly in a nice comfy chair so that I could take best advantage of it.
I was astonished by how much I could see. I identified all the major maria, the ejecta blankets of Copernicus, Kepler, and Aristarchus, the slight embayment of Sinus Iridum, Lacus Excellentiae, Grimaldi, the Riphaeus Mountains, hints of not quite resolved structure in the Archimedes area of Mare Imbrium, and a lot of other stuff. The richness and variation of detail gave me the impression that I was looking at topography, not just albedo features, which is a sensation I have never before had with a naked-eye view of the Moon. I hasten to add that I was of course not looking at topographic shading -- the Moon was only a few hours from full, so there were no shadows to be seen, and even if their had been, I doubt my eyes have resolving power sufficient to distingiush any. But even so, the sudden naked-eye awareness of the underlying topography was dazzling, and even a little spooky. If I had not already known, I would have suddenty discovered that there was another world up there, hanging luminous above the tree branches.
I tried talking some other partygoers through the list of features I had spotted. This is a test of both eyeglass prescriptions and eyes. Most everybody could see all the maria that I pointed out, of which Mare Humorum was probably the most difficult. But Lacus Excellentiae was a much more difficult target.
The reflection of the Moon was visible in our host's swimming pool, and I could see almost all the same detail in it. How odd that another world had come to take a dip, and how wonderful a hobby that lets us dive into the sky as easily as we dive into that pool.