There are three key reasons that NASA would not want to hidde the evidence or wouldn't want a ancient civilzation. One reason is that having a ancient civilzation would be a key thing to research. Another one is it would make the popularity and profits go up for NASA. The Third reason is that the face is two miles wide, and resembles a butte, from the camera's quality.

They wouldn't want to hide this civilzation, because they would have reasearch and more popularity. NASA's defenders say they wish there was a civilzation. The article stated this about the Nasa budget: "Meanwhile, defenders of the NASA budget wish there was an Ancient civilzation on Mars." They want there to be one but that isn't what it is.

NASA would get more donations and profit if this was true. This means NASA wouldn't want to deny it if it even was true. The reasoning of the conspiracy theorists are wrong saying that they want to hide this evidence, because they don't. This would enable them to accomplish farther space study and more information about an extra terristral civilzation.

The camera they used in 2001 compared to 1977 had a way better camera. Also they stated in the article "...on April 8, 2001--a cloudless summer day in Cydonia--Mars Global Surveyor drew close enough for a second look". This takes out the reasoning of the conspiracy theorists that their were clouds and shadows blocking the camera that made it appear as a butte in 2001 compared to when it looked like a face in 1977.

NASA has done extensive research on this topic and wished it was true. The facts prove it is not real, and how it would help NASA if it was. As the cameras have gotten better and people have resoned better it proves the Mars face was a natural mishap from shadows of the two mile wide butte. 