Humans have long been fascinated with the Moon, our closest celestial neighbor, perhaps formed by a collision between the Earth and the ancient planet Theia billions of years ago. The favored hypothesis is that Theia, named after the mother of the Greek Moon-goddess Selene, impacted the Earth, sending parts of both out into space. A debris ring formed, eventually coalescing into the Moon. A 2022 NASA simulation shows Theia as a golden orb about the size of Mars crashing into a larger orb, the Earth. Their molten bodies act as liquid, glomming and globbing, together and apart. Bits of both swirl all around. The large orb recomposes itself quickly, while two smaller ones form farther out in space. At first, there’s a thin line of plasma tying all three of them together. Then, the orb closest to the Earth suddenly returns to it — perhaps some of the Earth’s iron core? — the tether breaks, and the remaining, smallest orb becomes the Moon in a stable orbit around the Earth.

A 2022 NASA and Durham University simulation of the formation of the Moon.

It all could have happened another way — some planets capture their moons — but if it happened this way, then the Earth was really never alone. The Moon has always been with us.

Throughout history, some peoples have oriented their calendar around lunar cycles, or worshipped the Moon in preference to the Sun, given the Moon’s apparently larger size. Across many cultures, the Moon is associated with deities, femininity (like Mother Earth), the length of menstrual cycles, dreams, poetry, and love — la bella luna, arguably a major character in Moonstruck that animates the unexpected romance between different characters.

Sketch of a film poster by Georges Méliès for his Le voyage dans la lune (1902).

The Moon was featured in one of the first silent films, A Trip to the Moon (Le voyage dans la lune) (1902), inspired by Jules Verne’s From the Earth to the Moon (1865) and its sequel Around the Moon (1870). The film depicts a group of astronomers who are shot to the Moon in a giant bullet, which crashes into its eye. While seeking refuge below the surface, they encounter the Selenites, are taken captive, and eventually escape back to Earth. The film was a huge success and widely pirated in its day. It was also recreated in the music video for “Tonight, Tonight” by the Smashing Pumpkins, with the addition of Neptune treating the astronomers to an underwater concert.

A different voyage is offered in Laurie Anderson and Hsin-Chien Huang’s To the Moon, a VR installation that launches participants to an interactive lunar surface, which I was fortunate to see in January 2020. The terrain is irregular, littered with craters large and small, and the pitch blackness of space is never far away. Light, whether from swirls of stars in the distance or from the piercing rays of the Sun, haunts the landscape. I mostly spent my time there wandering, finding peace in the quiet and open space. I also remember feeling mildly terrified, as if I were at once completely alone and also being watched, just over my shoulder. Maybe it was the Selenites.

The Moon in tarot can be illuminating — without electricity, travel by night is facilitated by moonlight. It can also be a sign of danger, the unconscious, or hidden forces working against someone — the Moon has its far side, roughly half of its surface that is never seen by the naked eye from our vantage point on Earth. Moon cards, from the fifteenth century through Pamela Coleman Smith’s well-known illustration, depict a dog and a wolf howling up at the Moon, as if to announce a warning, while a lobster emerges from water, bringing new knowledge to the surface. 

Animals, too, are influenced by the Moon. Scorpions glow blue-green in the UV rays of moonlight, perhaps to warn predators or to aid their vision using the color they see best. Lions prefer to hunt on the darkest nights when their prey is more vulnerable. And, of course, there is the figure of the werewolf, a reflection of our own animalistic nature set free by the full moon.

Moon cards throughout history (left to right): Cary Sheet, Milan, c. 1499; Tarot of Marseilles, 1701–15; Rider–Waite Deck, illustrated by Pamela Coleman Smith, 1909.

Whatever its role, the Moon is relational. Its gravitational pull affects Earth’s tides. We see the Man in the Moon, a human face looking back at us. The Moon’s light is, after all, a reflection of the Sun. In fact, I’ve often observed that people with a particular Moon sign naturally align with someone of the same Sun sign, as if the Sun sign person just understands them and their innermost thoughts and motivations without much need for explanation.

Yet for all its power, the Moon is sometimes void, entering periods much like a retrograde planet or an eclipse, where its effects are inverted, malefic, or simply diminished.

As a celestial body like the Moon moves through a zodiac sign, there are moments where it forms aspects, or angles, with other celestial bodies, which themselves transit through different signs over time. These aspects can be mutually supporting or detrimental depending on the degree of the angle, the signs, or even the celestial bodies involved. For example, Great Conjunctions, which involve Jupiter and Saturn in close proximity, were regarded as omens — for good or ill — in ancient Arabic and medieval European astrology. The Great Conjunction of 1484 in Scorpio heralded the arrival of a “little prophet,” who was later taken to be Martin Luther, while the Great Conjunction of 1542 in Pisces was predicted to bring about a great transformation. This prophecy was dramatized as a great flood in the years leading up to the conjunction, spread through Europe with the help of new pamphlet printing technology of the time. Peoples readied themselves for a disaster that never came — though a peasant revolt did. Great Conjunctions happen only once every 20 years, due to the large orbits of the outer planets. Less dramatic conjunctions and other aspects give texture to the days, weeks, months, and years that a celestial body transits a sign.

There also comes a point in this transit where a celestial body will not form any more aspects while in that sign, and for that time, it is “void of course.” This is not unique to the Moon, but the Moon moves through all twelve zodiac signs rather quickly, in just 28 days, spending just over two days in each sign. The Moon’s small orbit creates more frequent opportunities for it to be void of course, a period that can last anywhere from a few seconds to several days.

Until recently, void moons were widely followed and discussed. In her essay on their history, J. Lee Lehman writes that “voids, like Mercury retrograde, the two bugaboos of modern astrology, both have the advantage of being easy to define and track, thereby making available these techniques even to non-astrologers, given a little bit of training in reading the tables.” Mercury retrograde is still discussed openly today, perhaps even more than in previous decades. But void moons are rarely mentioned anymore.

What does it mean that the Moon—so close to us in so many ways—regularly and perhaps even frequently is void?

Al H. Morrison popularized the notion of void moons in the 1960s, along with the view that presidential candidates nominated under a void moon lose the election. As it turns out, Nancy Reagan regularly consulted astrologer Joan Quigley about the timing of the president’s schedule, and Ronald Reagan used void moons to hold press conferences on hard or controversial topics. The next day, the issue seemed to be forgotten.

Morrison cautions against “decisions” during this time — really, the start of anything new — recognizing that everyday activities carry on through the void. Contemporary astrologers still warn against making purchases, signing contracts, getting married, having a first date, or starting a new project during a void moon. Outcomes seem unpredictable in the void, as if luck is suspended. But some moons may be more fortunate than others. Medieval astrologer Guido Bonatti exempted moons transiting Cancer, Taurus, Sagittarius, and Pisces from these effects. Cancer is ruled by the Moon, which is said to be exalted in Taurus — it performs best there, as if realizing its full power. Sagittarius and Pisces are ruled by Jupiter, whose luck seems to be incorruptible, even by a void moon. Bonatti also thought that the Moon is void until it comes into aspect with something, not just when it enters the next sign. That would make void moons last longer, perhaps mitigated by the Moon switching into an exempted sign.

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Hellenistic astrologers held the most restrictive views on void moons. With the zodiac wheel divided into 12 signs (30˚ in each sign), they thought a void occurs only when the Moon transits at least 30˚ (about 55 hours) without aspecting any planet, regardless of whether the Moon enters a new sign during that time. On this account, void moons happen less frequently, about as often as Mercury retrogrades. March 2025 had three void moons on this definition; sometimes, entire years have only one.

An intermediate number was given by seventeenth-century astrologer William Lilly, whose ideas have animated much of contemporary astrology. Each celestial body has a perimeter of influence, or “orb.” A square aspect is theoretically a 90˚ angle between two celestial bodies as seen from Earth. Accounting for the perimeters of these bodies, an actual square between them might be anywhere from 85˚ to 95˚, an orb of 5˚ in either direction. Most astrologers today use an orb of 6˚ for major aspects, though smaller orbs are associated with more significant events. Lilly’s orb was 10˚, making his aspects longer and void moons rarer, though not as rare as in the ancient definition.

However often we imagine a void moon to occur, it suggests a time when the celestial body has done its work in a sign (or not yet started). It’s a time for rest and reflection, like when the molten bits in the NASA simulation settle down after impacting one another. They begin to take shape, as if starting to understand themselves as separate entities for the first time, yet still held in a cosmic dance, hurtling through space in relation to one another.

As above, so below. Can we, too, be set free by a void moon? If the Moon speaks to our inner drives and darker forces, are we freed from those during a void moon — or perhaps free to explore them? Can we see this time as a necessary pause before or after taking action?

Even if void moons are frequent, they’re still quite brief. The moon may have just seconds before it starts forming new aspects with other planets. That’s a short breath, and rare enough to feel momentous.

SEE ALSO: “Void of Course,” The Astrology Dictionary; J. Lee Lehman, “The Void-of-Course Moon: From Linear Time to Lunar Time,” 2003; The Best of Al H. Morrison: Selected and Edited by Karen Christino (2023); Gustav-Adolf Schoener, “The Flood of 1524: The First Mass-media Event in European History,” Esoterica IX (2007): 166–78; Barrett Seaman, “Good Heavens! An astrologer dictating the President’s schedule?” TIME Magazine, May 16, 1988; Jatan Mehta, “How Planets Get Moons,” The Planetary Society, 2022; Frank Tavares, “Collision May Have Formed the Moon in Mere Hours, Simulations Reveal,” NASA, 2022.

Chris Alen Sula is a teacher and scholar living in Brooklyn. He is interested in technology, the occult, and cultural studies, and has been published in various journals and edited volumes.