In a 1961 episode of The Twilight Zone titled “The Invaders,” a woman’s cabin is besieged by tiny, humanoid aliens who immediately begin shooting her with little guns. The woman follows one up to a miniature spaceship and destroys it while he’s inside. Then, viewers see the label on the ship: “U.S. Air Force Space Probe No. 1.”

Turns out, that “alien” was actually a human—which is also the case with a mysterious six-inch mummy found in Chile.

Rumors of a tiny alien unearthed in the Atacama Desert have circulated for 15 years, because the details of the mummified skeleton seemed like something out of science fiction. It had an enlarged cranium and oversized eye sockets, like the Greys, a popular type of alien in movies, TV, and books. And, similar to the trope of aliens as “little green men,” the half-foot-tall skeleton was much smaller than the average human, and even had ten ribs instead of the typical 12, reports the New York Times.

But a little green man this was not. DNA analysis has since confirmed it was a female skeleton genetically linked to the local population that was buried about 40 years ago. Although the skeleton’s tiny bones were as mature as a six-year-old’s, it was more likely a fetus who was stillborn or died shortly after birth, reports National Geographic. Moreover, researchers have discovered that the skeleton had a previously undocumented bone disorder, according to an article published Thursday in the journal Genome Research.

Atacama Skeleton Discovery
This tiny skeleton, found in Chile’s Atacama Desert, was thought to be potential evidence of extraterrestrial life, but its true origins are also bizarre. (Credit: Bhattacharya S et al. 2018)

Ata, as the skeleton is known, has been in the spotlight before. In 2013, a UFO conspiracy theory film, Sirius, teased Ata in its trailer and stated ominously in a press release that the film would reveal “paradigm shifting physical evidence” about the skeleton. It was a bizarre promotional strategy, considering the film interviewed a scientist who had studied Ata’s DNA, and concluded that the skeleton was unambiguously human.

That scientists was Garry Nolan, an immunologist at Stanford University and co-author of the recent paper about Ata’s bone disorder. Nolan found that Ata had mutations in seven genes related to human growth. But her skull shape and rapid development in her tiny bones is likely linked to just one or two of these mutations, rather than all seven.

Stephen Greer, the conspiracy theorist behind Sirius, has refuted Nolan’s conclusions about Ata, telling National Geographic: “We don’t know what it is, but it most certainly is not a deformed human.”

But scientists like Nolan feel that the evidence is enough to return Ata to the place where she was found. Though researchers don’t know who her parents were, they note that the remains were buried with care in the Atacama desert, and should be returned out of respect for the people who laid them there in the late 1970s.