It’s no surprise that the United States Air Force is up to some pretty secretive stuff. Area 51, for example, is an Air Force-run facility and detachment of Edwards Air Force Base in nearby southern California. It’s public knowledge that the USAF tests some of its most secretive and cutting-edge technologies in Nevada’s Groom Lake and the Nevada Test Site, but little information about what goes on at these bases is actually made public. Still, there are some tidbits of information available to the public if you look in the right places. The military units which operate at these top-secret bases, for example, don’t always hide the fact that they’re up to some weird stuff out in the desert.

This week, Tyler Rogoway’s military technology blog The War Zone shared pictures of the official challenge coin of the USAF’s 72d Test and Evaluation Squadron Detachment Two, and the coin seems to imply that the unit revels in the fact its testing ground is steeped in UFO, alien, and otherwise spooky lore. The bizarre challenge coin, which can be seen here, is a collage of odd symbols, cryptic imagery, and mysterious slogans all of which point to the fact that this unit is up to some seriously shadowy work in the Nevada desert. What exactly was this unit trying to depict with the coin?

Challenge coins are small tokens of appreciation or commemoration issued by units of the military and often traded among service members. The most prominent aspect of this strange coin is a large B-2 bomber spanning the entire width of one of its faces. The 72nd Test and Evaluation Squadron Detachment Two is charged with testing and evaluating the B-2 Spirit aircraft, more commonly referred to as the Stealth Bomber. It’s believed that this single-wing aircraft is responsible for many “flying saucer” sightings due to its flat profile and near-silent operation. Surrounding the bomber is the unit’s cloud and lightning bolt insignia and a series of strange unknown symbols believed to depict antenna arrays at Area 51. The edge of the face contains the US Post Office’s motto of “neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds.”

The coin’s other face bears the motto ‘Denego, Decipio, Depopulor,’ Latin for “Deny, Deceive, Destroy,” and depicts the Las Vegas skyline with a cryptic map-looking image beneath it. The meaning of this image is unknown, but it appears to depict some sort of tunnel system, road map, or other similar structure. Superimposed on this image is a typical grey alien which appears to be scratching its head in disbelief as a B-2 flies over Las Vegas as a lightning bolt striking the ground before it. It’s a truly disconcerting image, and I encourage you to visit The War Zone to check it out and read Rogoway’s analysis of the coin and the history of the unit behind it.

Is this coin merely a tongue-in-cheek reference to the otherwordly folklore surrounding the USAF’s bases like Area 51, or might this coin be a way of hiding knowledge of higher mysteries in plain sight? What would be the gain in that, other than to laugh at us mortals down here in the dark? Like all things with these top secret units, we’ll likely never know.