Most mountain walled plains tend to fade away towards full moon. Plato is an exception to this rule, owing to the unusual dark basalt which has flooded its floor. Its large, dark oval becomes more prominent under a higher Sun, and can sometimes even be seen with the naked eye.

Photo: Thierry Legault. The full size original of this and other high definition lunar images may be seen at his High Resolution CCD Imaging site.

Inconstant Moon