Off to the charts. Sure enough, Rukl shows Rima Plinius just north of the crater, with one main trunk and two parallel lesser rimae (I only saw one line no matter how hard I looked).
Nothing running in a north/south direction at all, save for an indistinct dorsum that should have shown some breakage (but part of it was roughly in the right place. The rille was marked in the wrong place, but maybe close enough). Hmm.
Times Atlas comes out. Again, same features shown, just a bit more detail.
Logically, it would somehow be the main rima crossed by the wrinkle ridge, but it was close enough to the terminator that I would expect the ridge to show as they normally do, and the rille would be more dark than light.
I can't convince myself that what I saw was what is charted, as both my eyepiece impression and the crude sketch I made show it in utterly the wrong place.
I'm pretty sure it wasn't a lunar "crop cross," though.
Question: 2/3 of the way toward the south of the ridge, when it makes that pronounced S-bend, is the ridge not as tall from there south or is it that the S-bend makes the ridge more parallel to the sunlight and therefore there's just not as much shadow? It appears to me that the S-bend is a saddle point in the ridge.
On 4/14/98 at a little after midnight, sunset in Mare Serenitatis, right next to the Serpentine Ridge on the terminator the lit walls of dark Posidonius showed as a half-circle of light looping out from the bright part of the moon.
The light was so oblique that the north/south portions seemed almost like rilles, but they could be distinguished as dorsa fairly easily because they were (a) quite wide and obvious, and (b) I'm convinced if there were a rille that choice I'd know it by now!
|Chart 23||Moon-Lite Atlas for chart 24||Chart 25|