Since time unremembered the moon has held a special allure for humanity. From ancient civilizations spread across the globe there come myriad myths and legends associated with it. It has always seemed to have held some power over us, hanging there in the sky and inviting wonder, speculation, and mysteries. It is no wonder that we long sought to reach it, yet even upon stepping foot upon the moon's surface the mysteries have never really ended, and it poses many questions to us still today. Of course, in addtion to the scientific investigations into the moon such a mystical and mysterious place has also long drawn to it strange stories of alien bases and artifacts buried there, and one of the weirdeest of these is the notion that the moon is actually a hollowed out alien spaceship.
The idea that the moon in hollow is not particularly new. It was brought to the public consciousness in H. G. Wells' 1901 novel The First Men in the Moon, and appeared in numerous science fiction novels and short stories after that, but it was always some nebulous, fantastical concept that could never really be proven, much like the idea of alien cities on Mars, and so it long remained firmly lodged in the realm of fiction, strictly locked in the realm of debate and fanciful speculation. Yet the idea would not go away, and was given serious consideration by some, with the idea also thrown around that the moon might even be artificial in nature, placed there by powers beyond our comprehensiopn. This was only given more thrust by claims such as that by famed science fiction author Isaac Asimov, who noted that one piece of evidence for the artificiality of the moon was that it seemed to fit so perfectly with the sun to create perfect eclipses. He would say of this in 1965:
What makes a total eclipse so remarkable is the sheer astronomical accident that the Moon fits so snugly over the Sun. The Moon is just large enough to cover the Sun completely (at times) so that a temporary night falls and the stars spring out. The Sun's greater distance makes up for its greater size and the result is that the Moon and the Sun appear to be equal in size. There is no astronomical reason why Moon and Sun should fit so well. It is the sheerest of coincidence, and only the Earth among all the planets is blessed in this fashion.
It was all a popular notion at the time, yet still no more than wild speculation. However, the hypothesis that the moon might be hollow was given extra fuel in the late 1960s, when astronauts made a very peculiar discovery. In 1969, the United States carried out the Apollo 12 mission, during which the astronauts Pete Conrad and Alan Bean set up a Passive Seismic Experiment as a part of a larger series of moon experiments called the Apollo Lunar Surface Experiment Package (ALSEP), meant to shed light on the composition of the moon, setting up an array of seismometers around the landing site. On November 20, 1969, Apollo 12 deliberately crashed the Ascent Stage of its Lunar Module onto the Moon's surface; creating an impact equivalent to detonating several tons of TNT and triggered what’s known as a “moonquake.” At the time, NASA reported that the Moon rang 'like a bell' for almost an hour, which of course stirred up debate on whether the moon really was hollow after all, and when it was released in March 1970 in an article in Popular Science there was lots of talk on the idea that this was evidence of the moon being hollow, further propelling the wild theory.
Over the next several Apollo missions these seismometers would record numerous moonquakes, something seismologists had never seen before, and during some of these, in particular shallow ones, there were similar results, with the moon noticeably “ringing like a bell.” Scientists would end up explaining this through the differences in the texture, type and density of the planetary strata on the moon, but to conspiracy theorists this was just too good to pass up, and the Hollow Moon hypothesis really picked up some steam. In 1970, Soviet scientists Michael Vasin and Alexander Shcherbakov, of the Soviet Academy of Sciences really took it to the next level when they proposed that not only was the moon hollow, but that is was a spaceship created by alien intelligences. They explored this idea in an article called Is the Moon the Creation of Alien Intelligence?, which was published in the magazine Sputnik, and in which they claimed that the craters on the moon are mostly too shallow and have flat or even convex bottoms, which they took to be evidence that these meteors were smashing against some sort of armored hull beneath the ground. The two scientists backed their claim with scientific data, such as that some lunar rocks contained processed metals such as Brass, the elements of Uranium 236 and Neptunium 237, which they claimed cannot be found to occur naturally. The also cite earlier speculation by astrophysicist Iosif Shklovsky, who suggested that the Martian moon Phobos was similarly an artificial satellite and hollow.
Although there was no real evidence at all that the moon is a spaceship, the concept gained a lot of popularity and in as recently as 2005 it was the subject of a book called Who Built the Moon?, which postulates that it was perhaps not even aliens that built the moon, but rather time-travelling humans from the far future in order to observe the evolution of life on Earth. The hypothesis has gone on to be actively endorsed by such high profile conspiracy theorists as Jim Marrs and David Icke, and to this day it has its proponents, with new “evidence” often proposed, such as that some moon rocks have been discovered to be much older than rocks on the Earth, even though both were apparently formed during the same period, and it is often pointed out that it seems odd that we have not been back to the moon since the 1970s, and there has never been a base erected there even though it is within our power to do so. Proponents of a hollow moon ask why not? A typical argument for this was written in a piece on the site Exemplore, which reads:
When it comes to the moon we have to ask ourselves one question: Why hasn’t anyone been there in the past 40 years? We continue to study it, and we send probes to orbit, but nobody has set foot on the thing since 1972. Why not? When many of us were kids we imagined by now there would be colonies on the moon, or at the very least there would be science outposts and space stations. While it would surely be a challenge to keep a well-provisioned space station on the moon, it does seem like the next logical step in the progression of space exploration.
So why are we ignoring the moon? Is it really that boring, or is there something keeping us from going there? If there really is an alien civilization inside the moon we can only imagine their irritation when NASA astronauts started ringing their home like a bell and running around on the surface. Perhaps we were given a warning, or, more precisely, the major governments of the world were given a warning. To avoid hysteria, they’ve hidden the truth from the general population, but the message was clear: ‘You’ve seen all you need to see of the Moon. Move along.’
While it is true that there is much that we do not yet understand about the moon, mainstream scientists have thoroughly distanced themselves from the idea. It has been pretty conclusively shown that the moon is indeed solid, with evidence of the internal structure of the Moon overwhelmingly supports a solid internal structure with a thin crust, an extensive mantle and a small denser core, and all of the “evidence” shown for the moon being a hollowed out spaceship have been shown to have rational explanations. For instance, the anomaly of the sound of the moonquakes can be explained by the unique structure, density, and composition of the moon, as well as the lack of water in the environment there. Earth is also not the only planet with a satellite that orbits to create perfect eclipses, and this has been explained as well. Indeed, other data collected since spacecraft began to orbit or land on the Moon indicate that it has a thin crust, extensive mantle and small, dense core, just like Earth, although far less dense. In addition, based on the behavior of objects interacting with the gravitational field of the moon, we can determine its mass and calculate the density, which strongly rejects the notion that the moon could be hollow.
Yet, the Hollow Moon hypothesis still stubbornly persists, will all manner of evidence being thrown out to support it, although much of it has been patently debunked, and the idea of a hollow moon was recently brought back into the public consciousness by the 2022 Roland Emmerich film Moonfall, which was directly inspired by the Hollow Moon hypothesis and depicts the moon as a giant spaceship that threatens the earth. Is there anything to this at all, or is it just the wild musings of the same kind of conspiracy theorists who insist that the earth is flat of hollow itself? Although the moon is almost certainly solid and not a spaceship, the conspiracies swirl, and it further shows that this is a place that will long have wonder and fantastical ideas gravitate towards it.