Clear view of a "flying saucer".

On the night in question, I was on the back deck of my house testing a new telescope mirror on the nearly full moon. I noticed a bright yellow light about a third the size of the moon travelling west to east (overhead) and apparently decending at a steep angle. The color was exactly that of a yellow traffic light, i.e. sodium yellow. There were four red lights, like navigation lights, around the rim; one on the forward side, one at the trailing side and one on the left and right. They were flashing on and off in a clockwise sequence as seen from below. As it decended toward the east it grew larger and disapeared over the roof of my house. I ran through the house, grabbing 7x50 binoculars as I went. Out on the front porch, I steadied the binoculars on the porch railing and looked at the craft, now at tree-top height and no more than a quarter of a mile away. My view-angle was no more than 5 degrees upward. The yellow light was clearly emenating from the bottom of the craft, which was flat and a bit inset. The craft was well-lit by the nearly full moon in very clear weather and appeared smooth and metallic, like new magnesium or aluminum but not polished. No seams or fasteners were visible. The over-all shape was that of a saucer with a dome on top. Over-all diameter appeared to be between 10 and 15 meters, with the dome taking up a third of that. the dome was flat on top and radiused smoothly into the sides, which were flat in cross-section, and had four keystone-shaped windows that I could see from my viewing angle. The sides of the top dome were smoothly radiused into the body of the craft, which curved continuously downward, and rapidly decreased in radius at the edge, curving under to the bottom. There was no haziness at all, and appeared as solid and real as a Cessna 172 flying along. Speed was maybe 50 kph. The interior appeared lit like an office at night, white and bright. No persons were visible, but a white column was in the center of the interior and took up perhaps a quarter to a third of the diameter of the dome, extending (apparently) floor-to-ceiling, and this could have blocked my view of someone on the forward side of the dome. Or it could have been flying on autopilot. Anyone with the technology to build one of these things would be capable of building an autonomous autopilot.
Date is approximate.  PD