yes, xenon I think is correct because - I'll tell you why I think so too - If you click on the link to the NASA page and then click on Large image, it opens in another browser window. Find the 'thing" and scroll down further and you see another blue-ish blob on the same general position across the screen. This leads me to believe that it may well be a processing artifact and not something near the Lunar surface. Have a look and see what I mean?
This has nothing to do with anything, but I downloaded the image and it seemed to me that the craters were 'bumps' and not "dips". When this happens, rotate the image 180 degrees and for some reason my eyes see the craters as "dips" now ! I can generally find something strange in most of the Moon images and this one is no different, but the compression they apply makes everything seem 'blocky' and so the detail is hidden - except for feint hints only.
I thought I saw a long thing which was not included in a crater's shadow. That would have to mean that it was above the crater, but it is not really large enough with out massive enlargement and once you have that, you have the blocky bits too.
-- Edited by qmantoo on Sunday 7th of April 2013 06:35:11 AM