Since Mike posted this image I have been looking very closely at Carpenter. With the angle of the sun and the shadows cast along the inside of the southern edge of the crater, I can see a lunar formation that appears to be about 3-4 miles long and which runs towards the center of the crater (the edge of the formation that faces the southern crater wall is noticeably catching sun light and is brighter than the rest of it). Take a close look at the formation in Mike's photo (expand the image when you open it up -- it makes seeing this shape easier). Now, I did check LROC images, LOC photos, Google Moon, Rukl and the Virtual Moon Atlas and could not see anything resembling this except for the LROC site using the "WMS Browser" -- take a look, I have attached that image. Now, interestingly, if you look at Mike's image and the LROC WMS Browser image you can see what seems to be a small speck of lighter colored surface at the bottom right side of the formation -- it appears in both images -- it may be: (1) light coming underneath the formation (extremely unlikely), (2) the top of a peak in the shadow just catching the sun's light, or (3) just different albedo (but this is questionable since it appears in the dark shadow). But do take a look -- this is interesting and I would not have noticed it if it were not for Mike's very detailed, high quality photo.