This enlargement makes it evident that some triangular shaped object punched a hole through whatever thin surface was used for the fake model of the Mars surface.  The surface was probably something like paper mache or more likely a two ply material.  The backing was either paper or a thin cotton stiffened by sizing.  The top layer of the thin two ply appears to be some fuzzy material.  Along the lines where the material tore, you can see tufts or filaments of the material sticking out.  A few tufts of the fuzzy stuff are still resting on the torn paper backing hanging down in the hole.  This indicates that the bond between the two plies was not very strong.

    Some type of string or wire appears to be draped into the triangular hole.  It apparently created the effect of a valley as it came down to the triangle area from above.  Since the string or wire does not stand out in the valley area, perhaps the second ply was sprayed on after the basic ground terrain had been established with the first ply. 

    Go back to the photographic evidence page and click on the 200% enlargement of this triangle so you can see the number "4" typed or printed nearby.