As the terminator slowly moves over the crater Werner, light of the lunar sunrise begins to illuminates some of the highest lunar topography in the region which is between the craters La Caille, Purbach, and Blanchinus. The "X" feature is fully formed from the sunlight illuminating specific crater walls and ridges and common topography shared between these craters in approximately two hours and stands out in obvious contrast to the dark side of the terminator. This unique lunar event or should I say, optical event, lasts for about another two hours before being total surrounded by light from the lunar sunrise. At this time the lower topography of the area is illuminated as well and the "X" on the moon begins its transition back into hiding on the surface of the fully illuminated lunar landscape.
I first observed the event when I was just 15 years old, on June 12, 1978. However, at that time, my afocal photographs that I took through my 60mm refractor telescope were not in focus, my correspondence with Researcher, Dr. Daniel H. Harris of P.S.I. (Project Starlight International, Austin TX USA) ended, and I did not follow through with any official organizations or offices at that time.
As the years passed I made a few attempts to observe this reflection again, but never did see it. More years past and my telescope and participation in astronomy temporarily fell by the wayside. Left in my memory and imagination was the unexplained "X" on the Moon; the mystery of what I saw that night, and how it came to be, I thought might never be known. Not such a mystery it turns out, but a rather illusive reflection off some very high lunar topography as light from the lunar sunrise strikes the area at a low angle. However, this is the most striking optical lunar event of its type.
A somewhat elusive illumination, this event seems to have gone virtually
unnoticed until recently. Anyone with a telescope can observe the
formation of this interesting event as the terminator moves across the
moon surface and the sunlight strikes this area of the moons topography.
Those fortunate enough to have any one of the lunar software programs
available today can use the parameter of 1.2 sun elevation over crater
Werner to help predict when the feature will be illuminated.
Moon-Lite Atlas for chart 55 |