okaydockhe Okiscopey,
you are free to use the gifs that I put up for any revision you so choose. It is a free world after all.
Getting back to it. I was thinking that I would need to find the triangular shaped shadow that occupies the inside of the dominant crater in the image. The crater is of Copernicus. If I know the size of the crater then I get an idea of the size of the base measure of the shadow occupying the crater wall.
How do we get a crude measure of the the length of the shadow? We can scale the size of the crater to the size of the diameter of the Moon. To do this we simply stack copies of the crater across the diagram like rosarie beads across a persons' face.
I took an outside measure of the crater photo, so I ended up with a crater that is 1/30th the diameter of the Moon. I have attached a diagram showing the method that I used to establish the base length of the crater.
Knowing the size of the crater will enable me to know the size of the shadow which occuppies most of its' circumference. For now, I have found one length without resorting to a text which will tell me the correct size of the crater. I already know the correct size, but that size is unimportant because, the asteroid is only of significance to me.
http://img261.imageshack.us/img261/4...ithdotbkb3.jpg