The Cydonia Mensae is a region on the planet Mars. It separates the heavily-cratered southern regions from the smooth plains of the North. This region may once have been underwater, making Cydonia a candidate for coastal zone, though scientists disagree about the facts. However, one fact remains indisputable. Cydonia is covered with mesas, and those mesas have attracted a great deal of attention from scientists and laypeople alike.
One of these mesas, photographed in 1976 by Viking 1, appears to be an image of a face. This may sound is located at 40° 75 minutes north, 9° 46 minutes west. In early photographs, the image of a face is clearly visible. See photos at the end of this article.
For many, the discovery of this monument was cause for jubilation. Could this face be the remnant of a long-lost Martian civilization? Other features on the mesa may resemble pyramids or other buildings, which supporters believed was part of an ancient ruined city.
Today, the face on Mars is seen as an optical illusion. Further pictures taken by Viking 1 and Viking 2 have given us more photos to study. A selection of photos shows that the face on Mars appears and disappears depending on lighting conditions.
Photos of the Face on Mars, courtesy Wikipedia: