Face On Mars
The famous 'Face on Mars' can be seen at the top.
Cydonia is a region of Mars. The name originally referred to an albedo feature (distinctively coloured area) that was visible from earthbound telescopes.
Today, the name covers three named regions on Mars: Cydonia Mensae, an area of flat-topped mesa-like features, Cydonia Colles, a region of small hills or knobs, and Cydonia Labyrinthus, a complex of intersecting valleys. As with other regions on Mars, the name Cydonia was drawn from classical antiquity, in this case from Kydonia, a historic citystate on the island of Crete.
A group of Cydonian hills has attracted notoriety because one of them looks like a face under certain lighting conditions, while others resemble pyramids; the phenomena has attracted both scientific and popular interest.
Location
Cydonia lies in the planet's northern hemisphere in a transitional zone between the heavily cratered regions to the South, and relatively smooth plains to the North. Some planetologists believe that the northern plains may once have been ocean beds and that Cydonia may have been a coastal zone (though this is still uncertain).
Images
Cropped version of the original batch-processed image (#35A72) of the "Face on Mars".
The black dots that give the image a speckled appearance are data errors.
Cydonia was first imaged in detail by the Viking 1 and Viking 2 orbiters. Eighteen images of the Cydonia region were taken by the Vikings, of which seven have resolutions better than 250 m/pixel (820 ft/pixel).
The other eleven images have resolutions worse than 550 m/pixel (1800 ft/pixel) and are virtually useless for studying surface features. Of the seven good images, the lighting and time at which two pairs of images were taken are so close as to reduce the number to five distinct images.
When the image was originally acquired, Viking chief scientist Gerry Soffen dismissed the "face" in image 35A72 as a " of light and shadow". However, a second image, 70A13, also shows the "Face" and was acquired 35 Viking orbits later at a different "sun-angle" than the 35A72 image. This latter discovery was made independently by two computer engineers at NASA's Goddard Space Flight Center, Vincent DiPietro and Gregory Molenaar, who discovered the two misfiled images, Viking frames 35A72 and 70A13, while searching through NASA archives.
Public fascination
The occurrence of an object on Mars with a seemingly human face caught the attention of individuals and organisations interested in extraterrestrial intelligence and visitations to Earth, and the images were published in this context in 1977. Some commentators, most notably Richard Hoagland, believe the "Face" to be evidence of a long-lost Martian civilization along with other features they believe are present, such as apparent pyramids, which they argue are part of a ruined city.
Taken using the onboard HiRISE camera.
Pyramid-like structure informally known as the "D & M pyramid" (after Vincent DiPietro and Gregory Molenaar).
More than 20 years after the Viking 1 images were taken, a succession of spacecraft visited Mars and collected new data from the Cydonia region. These spacecraft have included NASA's Mars Global Surveyor (1997-2006) and Mars Reconnaissance Orbiter (2006-), and the European Space Agency's Mars Express probe (2003-). In contrast to the relatively low resolution of the Viking images of Cydonia, these new platforms afford much improved resolution.
For instance, the Mars Express images are at a resolution of 14 m/pixel (46 ft/pixel) or better.