BOSTON – A recent study by Harvard social science researchers suggests that aliens might have been living on Earth for some time. The research paper, which is still awaiting peer review, proposes that extraterrestrial life forms could be residing underground on Earth or within the moon. Additionally, the study posits that UFOs and other unidentified anomalous phenomena (UAP) might be evidence of their activities.

The study presents an “unconventional” explanation for UAP. The authors, from Harvard University’s Human Flourishing Program, which examines factors contributing to human well-being, suggest that UAP could indicate the presence of extraterrestrial life.

UAP are objects or phenomena that cannot be readily identified or explained by known human-made or natural sources. The researchers emphasize that in their study, the “A” in UAP stands for “anomalous” rather than the more common “aerial,” since some UAP are not only airborne but also travel underwater.

UAP have been reported in various forms, such as spheres, discs, triangles, and other shapes, ranging in size from small orbs to large craft. These objects often exhibit flight patterns and maneuvers that defy conventional aerodynamics, such as sudden changes in direction, high speeds, and hovering without visible propulsion systems.

Last summer, 36-year-old Air Force veteran David Grusch stirred media interest by claiming that a top-secret U.S. military program had recovered the wreckage of several fully intact unidentified aerial craft, some containing non-human pilots.

A 2023 report from the Office of the Director of National Intelligence noted 510 UAP sightings in 2022, up from 366 in 2021. Of these, 171 exhibited unusual flight characteristics or performance capabilities that require further analysis.

“Hypotheses for such phenomena tend to fall into two categories: a conventional terrestrial explanation (e.g., human-made technology) or an extraterrestrial explanation (i.e., advanced civilizations from elsewhere in the cosmos),” the Harvard researchers stated in the paper.

“However, there is also a third minority class of hypothesis: an unconventional terrestrial explanation, outside the prevailing consensus view of the universe,” they continued. “This is the ultraterrestrial hypothesis, which includes the ‘cryptoterrestrial’ hypothesis. This suggests that UAP may reflect activities of intelligent beings concealed in stealth on Earth (e.g., underground), or in nearby environments (e.g., the moon), or even ‘walking among us’ (e.g., passing as humans).”

The researchers explore four theories on how aliens might live among us. The first, the human cryptoterrestrials theory, suggests an ancient human civilization more technologically advanced than our own has survived in secret.

The second theory posits a technologically advanced non-human civilization that evolved on Earth in secret, possibly created by an ape-like hominid or some unknown intelligent dinosaurs.

The third theory suggests that future humans or aliens live secretly on Earth. The fourth theory involves “magical cryptoterrestrials,” similar to “earthbound angels,” compared to fairies, elves, or nymphs.

“The principal weakness of [the final theory] is its utter strangeness, particularly for readers accustomed to explanations within the bounds of the standard model of physics,” the researchers noted. “While belief in extraterrestrials is tenable, belief in fairies is not a live option for many scientists. Despite skepticism, the unusual nature of some UAP warrants genuine consideration with epistemic humility and openness.”

Most experts in the field, however, do not believe UFOs or UAP are evidence of extraterrestrial activity.

“These encounters capture the imagination differently for different people,” said Joshua Semeter, professor of electrical and computer engineering and director of the Center for Space Physics at Boston University, in an earlier interview with Newsweek. “As a technologist, I speculate that some form of advanced technology may be involved. But I believe it is human technology. There are next-generation propulsion systems that could explain the unfamiliar flight characteristics observed. For me, the leap to speculations about aliens is too far. However, it is important to keep an open mind as we solve this mystery.”

This story was reported by MSN.