I didn't know they had walls on the Moon! It is quite obvious that some rectilinear object is within a few yards of the astronauts. Could it be that the astronauts were not trained properly? They were busy looking for life, not walls! Is this a natural formation then? Why isn't it rounded off and smoothed down from aeons of micrometeorite bombardment? Wouldn't this get the attention of a geologist/anthropologist?