I googled "black line across the face of the moon" and saw that someone from this forum posted this same message in 2011, I think. Anyway, the way he described it was exactly what I saw. It was 6:10 pm, full moon in Albuquerque, NM, the moon was big as it was early and it was still light out. Suddenly, I saw this black line start on one side of the moon and made its way across the face of the moon and end disappearing as it gained in the other direction. And once it reached the other side it faded from view like it just went off the moon on the other side. I thought perhaps it was a shadow of something but it would have to be something really close to the moon to create that shadow. Was it a satellite? The moon was in the east and the sun setting in the west which would throw light on the moon and could create a shadow of something. It was like something was perhaps circling the moon and the way the sun was hitting it, it caused the object to cast a shadow on the moon as it passed by. Looked pretty cool. Thoughts?