Digital imagery analysis of unusual Martian surface features

Appl Opt. 1988 May 15;27(10):1926-33. doi: 10.1364/AO.27.001926.

Abstract

Image processing results in support of ongoing research into the origin of a collection of unusual surface features on Mars are presented. The focus of the investigation is on a mile long feature in the Cydonia region of Mars which resembles a humanoid face that was imaged by Viking orbiter in 1976. While the face has been dismissed as a trick of light and shadow by some, there remains considerable interest in this feature, which others believe was sculpted into the form of a humanoid face, and several nearby polyhedral objects which appear to be spatially aligned with it. Image enhancements of the face show it to be a bisymmetrical object having two eyes, a nose, and a mouth; fine structure in the mouth suggesting teeth are apparent in the enhanced imagery as well as crossed symmetrical lines on the forehead. Facial features are also evident in the underlying 3-D surface which was reconstructed using a single image shape-from-shading technique. Synthetic images derived from the 3-D model by computer graphics techniques suggest that the impression of facial features evident in the original Viking imagery are not a transient phenomenon; i.e., they persist over a wide range of illumination and viewing conditions.