Cydonia: a new angle on the Martian face
In the 1970s it was the stuff of legend. Dozens of conspiracy theorists believed that the ruins of an intelligent civilisation lay strewn across the surface of the Cydonia region of Mars. Their source was a 1976 image from the NASA Viking orbiter probe. It showed what appeared to be a face looking out into space, surrounded by rock formations that looked uncannily like pyramids. At the time astronomers quickly dismissed their appearance as an optical illusion but the myth of alien remains persisted.
Mars Global Surveyor looked at Cydonia again in the late 1990s and just as planetary scientists had said, all the structures turned out to have a natural origin. Now ESA’s Mars Express probe has imaged the region in colour and sent back pictures of the ‘face’ in unprecedented detail.
Although there is no evidence for extraterrestrial construction, the whole region is fascinating to ‘areologists’ (the Martian equivalent of geologists). Cydonia is in Arabia Terra, between the southern plains and northern highlands of Mars. Gentle slopes or ‘debris aprons’ around hills characterise much of Arabia and are made up of rocks and ice. In Cydonia these aprons are less common and the hills rise more abruptly from their surroundings. The face itself shows signs of the landslides that will eventually form a debris apron.