Clear skies look unlikely for our planned Public Open Night scheduled for Saturday. So here’s a look at Friday night’s Moon. I captured this with my camera and a telephoto lens and it turned out pretty well. I must say, however, that visitors viewing Luna through the Observatory’s grand old telescope get a much better view than I’m displaying here! Still, we’ll point out a few things here that we would mention if we were looking through the telescope… First, look along the edge of the Moon’s disk as it is contrasted against the blackness of space; note how it’s a bit uneven? The lumps in the disk’s edge are actually mountains and crater rims on the sides of the Moon’s globe! See the “smile” line on the inner edge of the Moon? That line divides the lit and unlit portions of the Moon and is called the terminator. In this, the waxing gibbous phase, the terminator represents sunrise on the surface. As on Earth, sunrise shadows are long and those long shadows and low-angle sunlight bring out details in the craters and mountains (for even greater detail, see this image from last month). The bright ray-lines projecting from some of the craters are light-colored material “splashed” out of the crater sites as they were formed by asteroid hits; they mark newer craters. Also note the central peak in at least one of the craters – material thrust upward as shock waves from collisions bounded back, inward, from the forming crater walls. Old Luna is full of amazing sights, if only we will see them!
Stephens Memorial Observatory 