The "Face on Mars" was not created by aliens and is just a natural landform because, the face was made by shadows from when the picture was taken.

Also, when Michael Malin and his crew took there photo on April 5, 1998 the picture was ten times sharper than the one the Viking took in 1976. Many people where not satified when the photo was tooken because it was winter in April '98 (a cloudy time of the year on the Red Planet) the camera on board MGS had too peer through wispy clouds to see the Face. Skeptics say that the alien makings where hidden by haze from the clouds.

On April 8, 2001 (a cloudless summer day in Cydonia) Mars Global Surveyor took a closer look. Michal and his crew caputed an extraodinary photo using there camera's maximum resolution. If there was an object or objects in this picture you would be able too see them. The picture actually showed an equlevent picture of a nutte or mesa (which are landforms common around the American West).

That is why the Face on Mars was not created by aliens but simply just another landforms like the ones we have on Earth.