Here is my take on the Goblin of Mars:
The above is the NASA image ( http://mars.jpl.nasa.gov/msl-raw-ima...000E1_DXXX.jpg )... resized to 800% and enhanced a bit to show details. NASA had stored the image as Q=070 (therefore this is not a "raw image"). As you can see, the 070 compression created square patterns in the image. The "teeth" are really just compression artifacts.
Here is another example of compression artifacts (click on link):
http://i.stack.imgur.com/KRmVZ.jpg
Explanation (click on link):
http://photo.stackexchange.com/quest...one-about-them
The original shown image in the following link ( http://www.ufosightingsdaily.com/201...-stunning.html ) was modified and enhanced to show what the author was trying to demonstrate... unfortunately, they obliterated the compression artifacts (in the "mouth") in order to make a more convincing image that the object is artificial in nature (I am not saying they were intentionally trying to deceive, they were just being a little zealous).
M