NASA's 'Face on Mars' Photo Turns 47 Today

This day in history: NASA's Viking 1 spacecraft took a stunning photograph of Mars on July 25, 1976, sparking a global debate over alien life. The photo, nicknamed "Face on Mars," seemed to depict a sculpture of eyes, a nose, and a mouth near the Red Planet's Cydonia region.

The mysterious "face," about two miles long, seemed to be looking back at the cameras, arousing widespread interest and skepticism. The photograph caused a commotion, spawning media headlines and books pondering the possible secrets of Mars, even though several scientists rejected it as just a simple Martian mesa with peculiar shadows.