Galle is a crater on Mars. It is located on the eastern rim of the huge impact basin Argyre Planitia. It is named after the astronomer Johann Gottfried Galle.
Galle is often known as the "happy face crater" because the illusion of a smiley is created by a semicircular mountain range and two smaller craters within the main crater. [...]
As the smiley is a key motif in the comic book Watchmen by Alan Moore and Dave Gibbons, the crater was used as a story location after the coincidence was noted by Gibbons. According to Gibbons, the similarity "was almost too good to be true. I worried that if we put it in, people would never believe it.
Wikipedia | Galle