Face on Mars
The Face on Mars refers to a photo of a feature that looks like a human face on the surface of the planet Mars, specifically in the area of Cydonia Mensae, an area of Mars adjacent to the border between the Northern lowlands and the Western Arabia Terra. The mensae are characterized by knobs and mesas (mensae is the plural of mensa, which means table). It was first discovered by the Viking 1 orbiter. NASA released the photo to the public and pointed out this cool trick of light, shadows, and low resolution orbital photography. However, true believers know that the feature was actually built by aliens and that NASA has been trying to cover that up (NASA's mission to search for evidence of extraterrestrial life or civilizations is actually a lie orchestrated by Reptoids). One of the most persistent supporters of this idea is Richard C. Hoagland.
Years later high resolution photographs have shown the idea to be false.
 Proponents' initial mistake
Besides the fact that proponents of the idea have no evidence of an intelligent designer, they also make an error that many anti-evolutionists make. Seeing a series of coincidences in a single area, they understand that the probability that these were created is small. From there, they assume that as the probability was small, it must have had a designer, ignoring the fact that the post-probability is exactly 1, as that is the way it naturally turned out. It is just as likely that the 'face' could have ended up two feet north of its current position. It is just as likely that all of these shapes could have ended up in a different area of Mars. It is less likely that Mars could have ended up covered in faces. However, none of these happened, as the only current situation happened. This is similar to the monkey typewriter theory.
 Why does it matter?
The human brain is surprisingly active when the eyes that belong to that brain see a face, practically screaming to the mind of the individual of which that brain belongs "Dude! That's a face!" Unless suffering from prosopagnosia, a person can not help but to see a face when viewing any shapes arranged to even remotely form a face. There would probably be fewer claims of a conspiracy or intelligent intent were a hill to form the shape of an elbow, a foot, or even a fairly distinctive hand giving the Earth a middle finger (*cough* Carina Nebula *cough*).
 The Face revisited
All this should have fallen by the wayside, as higher resolution images of the area have been made by other spacecraft since then:
- NASA's Mars Global Surveyor imaged the "Face" in April 1998, before it had even finished aerobraking into low Martian orbit. Due to the interest in the "face" NASA released the new photos which clearly showed it to be a mountain, although it does look a bit like an island surrounded by no water. This confirmed NASA's initial position that it was due to the light and the low-quality resolution of the camera on the Viking 1 that gave it the smooth appearance. The orbiter photographed the face again in 2001, when it was in its proper mapping orbit, allowing higher resolution images.
- In 2006, Cydonia Mensae and the "Face" were imaged by the European Space Agency's Mars Express orbiter. The images made with the High Resolution Stereo Camera were used to create a 3D model of the feature. (The HRSC is the same instrument responsible for the Hale crater images.)
- In 2007, the HiRISE camera on board the Mars Reconnaissance Orbiter took another image with the monster resolution of 25 cm/pixel. The "Face" still looked like a weathered mesa (hill).
 Happy Face crater
The face found in Cydonia isn't alone on Mars. The impact crater Galle is also known as the "Happy Face" crater because of its uncanny resemblance to, of course, a happy face. It's not difficult to see how this could come about. Craters are, generally, circular, and any two dots caused by additional caters or mountains can easily be mistaken for eyes (craters within craters are common on old surfaces that haven't been reworked through tectonics and erosion). With the addition of something vaguely shaped like a mouth, the odds of a crater existing that could be interpreted as a face approach certainty.
The Happy Face crater also appears in Watchmen, owing to the fact that the happy face is a recurring visual motif of the film and comic book.
 Faces on Earth
 See also
- Mars Global Surveyor Mars Orbiter Camera Release No. MOC2-283: Highest-Resolution View of "Face on Mars", 24 May 2001 (contains links to the previous releases since the first imaging of the "Face" by the MGS in 1998)