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The rocket scientist who summoned demons: The true horror story of Jack Parsons

In the winter of 1946, two men from very different walks of life walked into California's Mojave Desert together, where one of them became convinced an extraordinary experiment they had been conducting had finally succeeded.

One of the men was pioneering rocket scientist Jack Parsons, a self-taught chemist who helped establish what would become NASA's Jet Propulsion Laboratory, and whose innovations in rocket propulsion would help lay the groundwork for the Space Race that would erupt in the years that followed. His unlikely companion was none other than L. Ron Hubbard, then a science fiction writer who had yet to compose the writings that would form the underpinnings of the Church of Scientology that he later established.

Despite Parsons' work with rockets and his companion Hubbard's fictional writings about them, their work together in the early months of 1946 had nothing to do with rocket propulsion, spacecraft, or other technological innovations that would eventually carry humans to space. Instead, Parsons and Hubbard were engaged in an elaborate series of occult ceremonies at the time, whereby they intended to summon an elemental feminine goddess known as "Babalon" (not to be confused with Babylon) to help them bring an otherworldly entity into physical existence.

Their efforts, known today as the "Babalon Working," represent one of the most unusual affairs in American history, with tangential connections to the history of space exploration.

Given its strangeness, the episode has garnered attention from several scholars and historians over the decades, who have sought to understand a series of events at the intersection of science and the occult involving one of the most unconventional innovators behind modern rocket propulsion.

Rockets and magic

Parsons, born in 1914, would become a key figure in the early development of American rocket technologies by the 1930s and 1940s in California, ultimately helping establish what would become the Jet Propulsion Laboratory (JPL). His contributions included the historic experiments at Pasadena's Arroyo Seco on Halloween Day in 1936, which NASA now recognizes as the foundational experiments that launched JPL.

Very much in contrast with his scientific aptitudes, Parsons also cultivated an interest in ceremonial magic during this period. By the early 1940s, he had immersed himself within the California chapter of the Ordo Templi Orientis (OTO), the organization associated with the infamous British occultist Aleister Crowley and his religious philosophy known as Thelema. In 1943, Parsons became the new leader of the organization's Agape Lodge, which subsequently began operating out of his Pasadena residence on South Orange Grove Avenue.

Parsons' occult interests became particularly focused on the evocation of supernatural entities during this period, which the young rocket scientist seemed to genuinely believe could be manifested in the physical world through ritual practices. Ultimately, this led him to undertake an ambitious — and utterly bizarre — series of ceremonies aimed at conjuring what was supposedly one of Thelema's most powerful supernatural entities.

five men in white button-down shirts lay on the desert sand next to sandbags and wires held up on pylons

Seated left to right: Rudolph Schott, Apollo Milton Olin Smith, Frank Malina (white shirt, dark pants), Ed Forman and Jack Parsons (right, foreground) in 1936. Their early experiments in rocket propulsion in the California desert helped establish the field of modern rocketry. (Image credit: NASA/Public domain)

The Babalon Working

Parsons first became acquainted with L. Ron Hubbard in the summer of 1945, and shortly after meeting, Hubbard became a resident of the scientist's Pasadena home.

While Hubbard had no formal training in the occult arts, Parsons felt he demonstrated the kinds of aptitudes that would make him a promising partner for a serious ceremonial magic undertaking. Thus, in the first days of January 1946, the pair embarked on a series of rituals, which Parsons documented in a manuscript that later became known as The Book of Babalon.

"In the introduction to this text [Parsons] explained that the underlying philosophy for the Babalon Working is that the present age is under the influence of a violent force," noted University of Gothenburg scholar Henrik Bogdan in a 2016 article published in the journal Numen. "The invocation of Babalon was thus, according to Parsons, an attempt to prevent the world from being destroyed."

Specifically, Parsons believed the force of Babalon could be manifested in a specific woman. "In this sense, the Babalon Working was not only an exercise in ritual magic, but a deliberate attempt to bring a divine feminine force into human form," Bogdan notes. With this goal in mind, during the first two weeks of January 1946, the pair worked to invoke this divine feminine figure, associated with liberation and spiritual transformation according to Crowley's Thelemic system.

a man in a suit sits at a desk, holding a feather quill pen

Portrait of the founder of Scientology, science fiction writer L. Ronald Hubbard. (Image credit:  Mondadori via Getty Images)

High strangeness in the Mojave Desert

On January 18, 1946, Parsons and Hubbard traveled into the Mojave Desert, where, according to Parsons' later writings, a change in atmosphere involving their ritual work suddenly became apparent. Now believing their operation had been a success, Parsons declared their work completed, and the two returned to Pasadena.

Soon afterward, Parsons reported to Hubbard that his elemental mistress had seemingly manifested with the sudden appearance at his home of a blue-eyed, red-haired artist named Marjorie Elizabeth Cameron. A former member of the U.S. Navy's WAVES program, Cameron had been invited to Parsons' residence by a colleague who, like Hubbard, was also lodging there at the time. Upon seeing her, Parsons became convinced this was the elemental lover he and Hubbard had worked to conjure, thereby confirming that the Babalon Working had produced its intended result.

Soon, Parsons and Cameron began a relationship, and borrowing ideas from Crowley's 1929 novel Moonchild, Parsons now believed that his romance with Cameron could facilitate the incarnation of a supernatural force through the literal conception of a child using ritual sex magic. The result, Parsons believed, could help to bring about a transformative new dawn in humanity's spiritual development.

This phase of the Babalon Working mainly involved magic rituals and Enochian incantations performed by Parsons and Cameron, with Hubbard present and assisting (in addition to having proposed Rachmaninoff's "Isle of the Dead" as an eerie sonic backdrop for the occasion). For Parsons, the ultimate goal had been to conceive a "magical child" that would become the newborn Thelemic messiah.

a mustachioed man stands in the desert in a wool duster

A photo of Jack Parson's from John Carter's 1999 book, Sex and Rockets: The Occult World of Jack Parsons, attributed to the Jet Propulsion Laboratory archive. (Image credit: NASA/JPL)

Aftermath

Following completion of the rituals in late February 1946, Cameron left on a trip to New York, and Parsons returned to the Mojave Desert where he completed a short treatise entitled Liber 49, believing it to be a "channeled" fourth and final portion of The Book of the Law, Crowley's foundational Thelemic text.

Upon returning from New York, Cameron even claimed to have observed an unusual aerial object—something akin to what later became known as "flying saucers" in the summer of the following year—which she believed to represent the "war engine" referenced in Crowley's work.

Crowley, however, was considerably less enthusiastic about all this. Upon learning what Parsons, Hubbard, and Cameron had been involved with, the famed British occultist confided to a colleague in an April 1946 correspondence that "Apparently he [Parsons] or Ron or somebody is producing a Moonchild. I get fairly frantic when I contemplate the idiocy of these louts."

Ultimately, a growing divide between Crowley and Parsons would cost the rocket scientist his leadership of the Agape Lodge, prompting his departure from Crowley's OTO before the end of 1946. His relationship with Hubbard similarly dissolved due to Parsons' worsening financial situation. Nevertheless, Parsons soldiered on, marrying Cameron in October 1946 and continuing his efforts to usher in a new spiritual age.

On June 17, 1952, Parsons' unusual life ended prematurely when an explosion occurred in his home laboratory, resulting in fatal injuries. He was only 37 years old. Questions still surround the circumstances of his death; while it was ruled an accident, there have been allegations that it was suicide or even a murder.

a police officer stands in a burned-out room with overturned furniture and destroyed walls

Pasadena Police Department officer Ernie Howard at the scene of the explosion that killed Jack Parsons. (Image credit: Public Domain/Los Angeles Times)

The strange legacy of Jack Parsons

During his short life, Parsons still managed to make significant contributions to the science of rocket propulsion, securing a place in the history of American space exploration — albeit one that is often overshadowed by the interest historians and scholars have taken in his occult activities.

Nonetheless, Parsons remains a key figure responsible for helping lay the early foundations for what would become America's space program. Although decades before NASA would begin sending its spacecraft in pursuit of answers to cosmic mysteries, one of its early technological pioneers had been seeking answers to such cosmic questions in a very different way: by exploring the boundary between our physical world and the supernatural realms beyond.

Bibliography

Anthony Testa, The Key of the Abyss: Jack Parsons, the Babalon Working and the Black Pilgrimage Decoded (2006), p. 128.

"Babalon Working." Occult Wiki. Accessed Oct. 29, 2026.

Bogdan, Henrik. "The Babalon Working 1946: L. Ron Hubbard, John Whiteside Parsons, and the Practice of Enochian Magic." Numen, Vol. 63, No. 1, 2016, pp. 12–32.

Carter, John. Sex and Rockets: The Occult World of Jack Parsons. New edition. Feral House, 2004.

Josephson Storm, Jason Ānanda. "Sex, Magic, & Rockets or the Implications of the Babalon Working for Theories of Belief and Rationality." Method & Theory in the Study of Religion, Vol. 37, 2025, pp. 323–335.

Riggins, Marleigh. "Shocktober: Babalon Working." LAist, Oct. 26, 2004.

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What causes mysterious long delayed radio echoes in Earth’s atmosphere?

In 1927, Norwegian civil engineer and amateur radio operator Jørgen Hals made an unusual discovery: while monitoring transmissions from a shortwave radio station in Eindhoven, The Netherlands, he began hearing odd, "delayed" radio echoes, arriving approximately three seconds after the original transmissions, that sometimes accompanied the station's signals.

"From where this echo comes I cannot say for the present," Hals wrote of his peculiar discovery, adding that he could "only confirm that I really heard it."

Almost a century after Hals' discovery, the exact cause of this unusual phenomenon — known today as long delayed echoes, or LDEs — remains unknown. Their baffling nature has prompted a range of potential explanations, most of which focus on a variety of unexplained natural phenomena occurring in Earth's atmosphere. However, a few more far-out possibilities, including potential evidence of extraterrestrial technology, have also been considered.

What do we know?

A curious discovery

The enigma of long-delayed echoes has perplexed scientists since their initial detection by Hals, who at the time reported his odd findings to Norwegian physicist Carl Størmer. This prompted an investigation by Størmer with physicist Balthasar van der Pol, during which the duo was able to reproduce the phenomenon but were unsuccessful in determining its cause.

Since those early observations, ongoing reports of long-delayed echoes have continued to be recorded. Under normal conditions, radio echoes occur whenever a radio signal reflects or "bounces" off an object, although other conditions such as signals traveling through a delayed path can also cause echoes to occur.

Long delayed echoes, by contrast, are generally characterized by radio signals that return after more than 2.7 seconds following their original transmission, although the terminology has sometimes been applied more broadly.

Complicating investigations into this unusual brand of radio phenomena over the years has been their unpredictable nature, along with significant reported variances in the timing and nature of the delays, which has made it difficult for researchers to narrow down a single cause.

Possible explanations

Despite the challenges presented by this unique class of space mysteries, there are several theories that have been put forward over the years about what could cause long-delayed echoes.

In the mid 1980s, researchers R. J. Vidmar and F. W. Crawford conducted experiments in Alaska that aimed to detect long-delayed echoes, which built on earlier research they published involving possible detections in 1970. According to their findings at the time, Vidmar and Crawford hypothesized that radio signals could be captured between ionized layers in the atmosphere and "guided" over long distances.

More recently, University of Oslo researcher Sverre Holm has advanced a similar concept that he calls magnetospherically ducted echo (MDE), in which radio waves may become trapped within electrically charged regions of Earth's upper atmosphere and guided along magnetic field lines extending far into the magnetosphere. Under certain conditions, these signals may reach as far away as the opposite hemisphere before they are "bounced" back toward Earth, resulting in the delayed echo effect.

According to Holm, MDE "is the best understood mechanism for long delayed echoes" out of five promising explanations he outlines, adding that based on the MDE model, such long delayed echoes "can be predicted to what seems like about 5 ms accuracy using a simple model for the magnetic field lines."

Still, one problem that arises involves the relatively short delays associated with this mechanism, which may not necessarily account for the much longer, multi-second echoes reported in some historical observations. Since radio waves travel at close to the speed of light, a signal could theoretically cover distances equivalent to the planet's circumference several times in a single second. While this doesn't prove the signals actually followed such paths, it does imply that some of the reported instances of long-delayed echoes might correspond to dozens of journeys around the planet.

Speaking with Space about historical cases involving much lengthier long-delayed echoes, Holm was clear in expressing that the MDE theory also has its limitations.

"In my view," Holm told Space in an email, "Magnetospheric Duct Echoes cannot [account] for those historical LDEs at all."

yellow gases swirl near a blue orb surrounded by a blue, wispy cloud

Earth is surrounded by a giant magnetic bubble called the magnetosphere, which helps protect the planet from radiation released by the sun. (Image credit: NASA)

To illustrate this, Holm points to two primary differences. First, the historical echoes were detected at approximately 9.55 MHz, well above the 1–4 MHz frequency range typically associated with MDEs. Additionally, historical LDEs reportedly exhibited delays ranging from 3 to 30 seconds, whereas MDEs generally produce delays of only a few hundred milliseconds.

By contrast, "MDES are only a few hundred milliseconds," Holm explained, meaning that they cannot account for all the characteristics of the earlier historic observations of long-delayed echoes.

Other theories that might be capable of filling some of the gaps in the long-delayed echo mystery include the idea that electromagnetic radio energy could be coupled into slower plasma-wave "modes" while traveling through Earth’s upper atmosphere, which, according to Holm’s review of the earlier work by Vidmar and Crawford, could potentially create much longer delays than ordinary radio propagation would allow.

After this proposed coupling into a plasma-wave mode, the signals may be converted back to ordinary electromagnetic signals and bounced back down to lower levels of Earth's atmosphere. Finally, a similar line of investigation has looked at whether clouds of plasma originating from the sun might also be able to produce the well-characterized echo effect.

What remains unknown?

Extraterrestrial origins?

Although scientific research has identified several promising explanations for long-delayed echoes, the mysterious nature of these events has also inspired more speculative theories over the decades, including some involving the search for extraterrestrial intelligence.

This unique dimension to the LDE mystery has its roots in the theories of Australian physicist Ronald Bracewell, who was the first to propose the idea that autonomous interstellar probes might be used by an advanced civilization as a means of establishing contact.

According to Bracewell, the initiators of such a hypothetical contact scenario might choose to reveal their presence by intercepting and re-transmitting radio signals rather than engaging in direct communication. Carl Sagan explored a similar concept in his novel "Contact", in which transmissions from the 1936 Olympics — the earliest broadcast signals to leave Earth's ionosphere — are intercepted and rebroadcast back to Earth as a data-encoded message originating from the Vega system.

However, more than a decade before the publication of Sagan's famous novel, Scottish writer Duncan Lunan attracted international attention for his 1973 article in the journal "Spaceflight" outlining his belief that he had successfully decoded a radio message dispatched from an extraterrestrial probe. According to Lunan, the initial detection of this "hidden" alien signal had taken place decades earlier in 1927, with the famous discovery of long-delayed echoes by Jørgen Hals.

Lunan's theory essentially went like this: an extraterrestrial civilization in the Epsilon Boötis system had deployed a hypothetical autonomous communications probe (known as a Bracewell probe) to Earth in the distant past, which had been comfortably orbiting in one of Earth's gravitationally stable Lagrange points for thousands of years.

Using the original long-delayed echo detections from Hals and Størmer's research decades earlier, Lunan placed the transmitted sequence on a vertical axis, while placing the recorded echo delay time on a horizontal axis, revealing what he believed to be a view of the constellation Boötes as it might have looked 15,000 years ago — right around the time the suspected space probe would have been dispatched to Earth.

a spacecraft shaped like a three-pronged star above a striped planet

A visualization of NASA's Juno probe orbiting Jupiter. Some scientists have proposed that distant alien civilizations might send autonomous interstellar probes to our solar system as a means of establishing contact. (Image credit: NASA/JPL-Caltech)

Despite Lunan's imaginative theory, an alternative hypothesis proposing a natural cause behind long-delayed echoes was subsequently advanced by Anthony Lawton, which ultimately garnered an award from the British Interplanetary Society. By 1976, Lunan had withdrawn his ideas in an article published in the Journal of the Society of Electronic and Radio Technicians, although he would eventually revisit a version of the theory in the 1990s.

The mystery continues

While few modern researchers seriously consider extraterrestrial hypotheses to explain long-delayed echoes, these obscure phenomena remain intriguing, even as ongoing research sheds light on their possible causes. Explanations such as Sverre Holm's magnetospherically ducted echo model offer promising mechanisms that may account for at least some of these unusual signals, although important questions remain unanswered.

For now, long-delayed echoes serve as a reminder of the challenges of studying electromagnetic phenomena, and how even seemingly familiar aspects of our physical world can harbor mysteries that resist straightforward explanations, even after nearly a century of investigation.

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Did a giant object collide with Earth to form the moon?

For as long as humans have watched the night sky, we have wondered about the moon, pondering everything from its alien appearance to its influence over phenomena on Earth such as ocean tides, climate stability, and even the natural rhythms of many organisms.

Among the many questions we have about Earth's lone natural satellite, one remains preeminent: what are the moon's origins, and how long has it orbited Earth?

Today, the leading theory among astronomers is that deep in our planet's past — perhaps within roughly the first 100 million years of solar system history — Earth collided with a planet-sized object, creating the moon within a period that may have been as short as just a few hours. Known as the giant-impact hypothesis, this proposed event involves a hypothetical Mars-sized protoplanet astronomers call Theia. The material ejected into orbit by the powerful impact in question would have accumulated afterward, forming the moon that we observe today.

What do we know?

Birth of a lunar origin hypothesis

The evolution of this striking solution to one of the moon's most enduring mysteries goes back to 1946, when geologist Reginald Aldworth Daly was among the first to suggest that an impact event might explain the formation of the moon.

Before Daly, scientists had been leaning toward theories that involved Earth's rapid spin billions of years ago, when each day may have at one time lasted as little as 2 or 3 hours. Decades later in the 1970s, researchers William Hartmann and Donald Davis developed their own models involving collisions of large bodies left over from planetary formation, which could collide with younger planets.

Building on such ideas, other researchers went on to propose similar scenarios between the early Earth and a Mars-sized object. Early in the following decade, the concept eventually claimed its place as the leading lunar-formation process during a landmark conference held in Kona, Hawaii, in 1984.

two large orbs collide, creating an explosion of fire and large rocky objects

Earth's moon is thought to have formed when a Mars-sized object, called Theia, slammed into the proto-Earth more than 4.4 billion years ago, blasting out material that later coalesced into a large satellite as depicted in this artist's illustration. (Image credit: NASA/JPL-Caltech)

Evidence of a planetary-scale collision

The popularity of the giant-impact hypothesis can be attributed to the multiple lines of evidence supporting the impact scenario. For instance, researchers have long recognized the similar stable-isotope ratios between both moon rocks and those from Earth, strongly suggesting a link between their origins.

Additionally, the unusually high angular momentum (or spin) of the Earth-moon system, when compared to observations of other rocky planets, also could be explained as one of the effects of a massive collision.

Further clues can be found in the moon's composition, which reveals a relatively small iron core and lower density. This is significant to astronomers, since a hypothetical giant impact would have seen the suspected Theia protoplanet's metallic core merging with the young Earth's interior — meanwhile, lighter mantle and crust material from both worlds would have become dislodged and blasted into orbit, eventually helping form the moon.

Another important piece of evidence involves the relative depletion of volatile substances (a chemical that easily turns into gas or vapor at room temperatures) in lunar material, which again suggests that it might have been lost during an extremely energetic event, an idea further supported by evidence that the early moon once possessed a substantial magma ocean.

an ocean of magma on the moon

Illustration of the young Earth-Moon system. The Earth had recently formed when it was struck by a protoplanet, called Theia, roughly three times the size of Mars. Debris from the impact went into orbit where it quickly coalesced to form the Moon, probably within just a few thousand years. Initially the Earth and moon were much closer together than they are now, and spinning more quickly. In this depiction, debris from the collision continues to rain down on both worlds. (Image credit: Mark Garlick/Science Photo Library/Getty Images)

What remains unknown?

New research expands on the Theia hypothesis

Still, several significant questions remain, including what precise conditions led to the impact, and how the resulting planetary material evolved into the moon as it appears today.

Recently, a new study by Adeene Denton of Southwest Research Institute and colleagues at the University of Arizona's Lunar and Planetary Laboratory put a new spin on the Theia hypothesis, suggesting that the suspected ancient impact may have been significantly influenced by the heat and physical strength of the two colliding bodies.

The team's findings challenge some long-held views about the giant-impact hypothesis, while lending new support to others. For instance, the team's simulations revealed that while some impacts lead to the creation of a disk of debris that later coalesces into a moon, under other conditions, simulations support the idea that the moon could have been formed in a remarkably short period of time — perhaps within around five hours.

However, one of the primary issues with determining the exact conditions of the giant-impact hypothesis involves the ongoing debate over the moon's age.

"There is a large controversy regarding the age of the moon," said Dr. Erik Asphaug, a planetary science professor at the University of Arizona's Lunar and Planetary Laboratory and one of the new study's co-authors.

A view of the moon in the foreground with a small Earth in the background.

Earth sets over the moon's curved limb in this photo captured by the Artemis II crew during their journey around the far side of the moon. (Image credit: NASA)

In an email to Space, Asphaug explained some of the issues arising from this, since current estimates place the timing of the moon's formation anywhere from around 40 to 120 million years after the formation of the solar system. Therein lies part of the issue, according to Asphaug, who says this timing could have significant implications for models of the Theia impact.

If it had been an earlier collision, Asphaug says this would have involved a hotter Theia due to the greater degree of radiogenic heating; by contrast, a later impact would have meant a cooler and stronger Theia.

"I don't think we know enough yet to say the moon (and by corollary, the Earth) formed this way or that way," Asphaug told Space. "But knowing how temperature affects the result opens up a new dimension for viewing the problem, and that is always helpful because it shifts our frame of reference, like getting out of the car to have a walk around."

A lunar enigma in time and space

For researchers like Asphaug, understanding the moon's formation requires looking at it as more than just an event in space, but also as one in time. Doing so allows comparisons between three different metrics: isotopic decay, temperature-dependent material strength, and the geological record of debris striking other planets — a process through which he believes tighter constraints could be placed on precisely when the moon-forming impact might have occurred.

Adeene Denton, the study's lead author, also emphasized the introduction of the time component her team's research brings to the table, telling Space in an email that the outcome of the moon-forming impact could have depended significantly on the timing of the collision.

"Before, scientists have generally assumed that the outcome of the collision will be the same regardless of when it takes place," Denton wrote. "But now we know that temperature's effect on material properties, which is dictated by how old and/or cold the proto-Earth and Theia might be, alters things substantially."

By connecting impact simulations to data related to the moon's geochemical record, as well as models of early solar system formation, Denton thinks her team's work could help scientists better constrain precisely how and when the moon formed.

The mystery continues

For now, in terms of which possible scenario — an earlier or later collision event — emerges as being the most likely, Denton says it's still difficult to say.

"It depends on which scenarios for solar system formation you favor," Denton told Space.

"I am generally in favor of an earlier formation of the moon, consistent with a rapid planet-building phase in our solar system," Denton said, "but we can't neglect the possibility that the moon formed late."

While much work remains to be done, Denton and Asphaug believe their findings help significantly advance present efforts to resolve some of the questions about the giant-impact hypothesis — a few of which have lingered now for many years.

For Asphaug, however, such lingering questions may simply be part of the scientific process.

"Science has a way of wandering around for a long time until finally it all comes to focus," Asphaug said.

"I believe that will happen, in part thanks to this work, in the coming decade."

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What caused a mysterious atmospheric explosion in Siberia in 1908?

Fire erupted in the morning skies over Siberia on June 30, 1908, as an atmospheric explosion occurred that remains unmatched by any similar event in modern history.

That day, at approximately 7:15 a.m. local time, observers in Siberia's remote Tunguska region became witnesses to the entry of a brilliant fireball into Earth's atmosphere, trailing smoke across the dawn sky and culminating in a flash brighter than the sun itself. Within seconds, the explosion and resulting shock waves that followed reportedly knocked some members of the nearby Indigenous Evenki population off their feet, and caused damage to dwellings and livestock, while seismic instruments hundreds of miles away logged tremors caused by the blast.

The blast produced enough energy to flatten a significant stretch of the Siberian wilderness, marking an event that still serves as a cautionary tale — and a major point of reference — for modern planetary defense efforts. Yet some questions remain about exactly what happened, and what the implications are for future potential Tunguska-scale events. For many years after the events of that day, the cause of the blast — known today as the Tunguska event — remained unknown. With time, a likely culprit emerged: scientists now believe a small asteroid, estimated to have been just 130 feet (40 meters) in diameter, exploded after entering Earth's atmosphere.

What do we know?

Unraveling the Tunguska Event mystery

Remarkably, scientists wouldn't get a firsthand look at the destruction caused by the Tunguska blast for almost two decades, due primarily to the extreme remoteness of the blast location. Further complicating scientific investigations were the First World War, the Russian Revolution, and the ensuing civil war.

One of the earliest attempts to reach the blast site was initiated in 1921 by Soviet geologist Leonid Kulik, who failed in his first effort, but did eventually make his way to Tunguska six years later. Upon arriving, the devastation caused by the event was unmistakable even after nearly two decades.

trees flattened in parallel rows

Trees felled by the explosion of a meteorite in Tunguska river region of central Siberia, (4 miles) 7 km to the north of the epicenter of the 1908 explosion. This picture was taken in May of 1929. (Image credit: Sovfoto/Universal Images Group via Getty Images)

Curiously, at the blast site's presumed epicenter, a small area of unaffected trees remained standing, albeit stripped of some of their bark and branches. The surrounding countryside, by comparison, was littered with large numbers of trees that were toppled as the shock waves produced by the exploding asteroid high above radiated downward.

In the decades that followed, additional assessment of the site that included expeditions and aerial surveys, primarily during the 1950s and 1960s, revealed another curious feature: a distinctive hourglass- or butterfly-shaped destruction zone spanning well over 800 square miles (2,070 square kilometers), with millions of trees estimated to have been flattened. Yet most curious of all had been what investigators did not find; despite a blast zone of this size, there was no evidence of an impact crater at Tunguska.

people on horseback crossing a small river

Professor Leonid Kulik who, in 1938, led a scientific expedition into the Siberian taiga to investigate the site of the Tunguska meteorite. Here, Kulik is seen crossing the Khushmo river on horse back 4 miles (7 km) from where the meteorite fell in 1908. (Image credit: Sovfoto/Universal Images Group via Getty Images)

An airburst over Siberia

What the evidence seemed to suggest was that an explosion had occurred not on the surface following a massive impact, but instead high in Earth's atmosphere — probably as much as several miles above the Earth — as tremendous aerodynamic stresses caused the object to fragment and release its energy before reaching the ground.

A longstanding debate about the Tunguska object has centered on whether it was more likely an asteroid or a comet, although today, most evidence appears to favor an asteroid. Among the clues supporting an asteroid origin are mineral and chemical signatures identified in material collected from the region that researchers have argued are consistent with a stony or carbonaceous asteroid. However, identifying physical remnants definitively associated with the Tunguska object has remained challenging.

What remains unknown?

A warning from the sky?

While the Tunguska event remains an enigma in some ways, it also offers modern researchers an opportunity to study one of the rare recent examples in Earth's geological history of a large-scale cosmic airburst.

Deeper in Earth's past — around 66 million years ago — a six-mile-wide (10 km) asteroid struck what is now Mexico's Yucatán Peninsula. The impact created the 120-mile-wide (190 km) Chicxulub crater in a cataclysmic event that drove mass extinctions across the planet, eliminating nearly three-quarters of the species that thrived on Earth until that time.

Of course, even objects orders of magnitude smaller than the object that created the Chicxulub crater can pose a danger to Earth. Although the object that struck Earth 66 million years ago is believed to have been as much as 200 times wider and millions of times more massive than the suspected asteroid that exploded over Siberia in 1908, estimates indicate that a Tunguska-scale event would be capable of killing millions if it occurred today over a city the size of New York.

Such estimates aren't based entirely on theory, either. In February 2013, planetary scientists were given a dramatic opportunity to gauge the effects of such an event when a previously undetected 60-foot-wide (20 meters) asteroid exploded after entering Earth's atmosphere over Chelyabinsk, Russia.

The resulting blast, which released energy equivalent to an estimated 500 kilotons of TNT, was captured on cameras throughout the region as it damaged buildings and caused injuries to more than 1,000 people, mostly due to flying glass from windows that were shattered by the blast wave.

trees flattened in parallel rows

Siberian taiga forest that was flattened by the blast from the Tunguska meteorite near where the meteorite fell in 1908. This picture was taken during professor Leonid Kulik's 1938 expedition to investigate the event. (Image credit: Sovfoto/Universal Images Group via Getty Images)

A wake-up call for planetary defense

Because of events like Chelyabinsk and Tunguska, planetary scientists have worked to expand initiatives that detect and monitor potentially hazardous near-Earth objects (NEOs) that could become a concern in the decades ahead.

Still, despite such efforts having been in effect at the time, the Chelyabinsk event represented an example of a potentially dangerous NEO that effectively managed to sneak up on us. Fortunately, despite the damage that was caused, things could have been far worse. But will we be so lucky next time?

To help mitigate such concerns, in 2016 NASA established the Planetary Defense Coordination Office to help align its efforts with those of its international partners and develop more advanced methods of identifying and tracking any NEOs that could pose an impact threat.

Then in 2022, NASA's Double Asteroid Redirection Test (DART) demonstrated the use of a spacecraft as a kinetic impactor, which was intentionally sent on a collision course with Dimorphos, the small moon of the asteroid Didymos, which altered Dimorphos' orbital period around its companion by approximately 33 minutes. Such technology could one day prove to be vital if another potential Tunguska-type object were found to be on a collision course with Earth.

workers repair a broken brick wall

Workers repair a power line near the wall of a local zinc plant which was damaged by a shockwave from a meteor in the Russian city of Chelyabinsk, on Feb. 15, 2013. (Image credit: OLEG KARGOPOLOV/AFP via Getty Images)

The mystery continues

Fact, fiction, and planning for the future

Given the questions that remain about Tunguska, as well as the misrepresentations and persistent myths surrounding it, several scientists have also worked in recent years to combat misinformation about the 1908 event.

In a paper published in March 2026 in the journal Meteoritics & Planetary Science, authors Mark Boslough and colleagues noted that future planning for evacuation plans and other mitigation efforts "depend critically on our ability to model these events, which depends on our understanding of the governing physics, which in turn is validated by sparse data on real events such as Tunguska."

"If people do not have confidence in the models on which evacuation plans are based, they could lose their lives," the study's authors warned.

More than a century after it occurred, June 30 is now recognized as International Asteroid Day, commemorating not only the blast's anniversary, but also the need for awareness of the dangerous potential future similar events could present.

Tunguska therefore remains a source of fascination for scientists, as well as an opportunity to better understand — and to prepare for — any potential future threats posed by similar objects, should one eventually be found on a collision course with Earth.

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Did the Soviet Union really fire a cannon from a space station?

Military officials in the U.S. and other nations have increasingly warned about the potential for conflict in space in the coming years. While many would perceive the current push to militarize space as a concern primarily for modern military thinkers, there is a far deeper — and at times, a surprising — history of warfare technologies developed for use in outer space.

At the height of the Cold War, one particularly unusual early application for space warfare was pursued by the Soviet Union, which involved mounting a rapid-fire cannon aboard a secret military space station. The weapon was reportedly developed for the Soviet-era Almaz military space station program, an ambitious Cold War-era initiative that sought to leverage cutting-edge orbital technologies of the day to enhance Moscow's military reconnaissance capabilities.

At the time, Soviet officials were concerned that the United States was already developing spacecraft that could approach, investigate, and either capture or disable Moscow's sensitive satellites. The natural response to such concerns was to develop defense systems capable of neutralizing such threats — and the result became legendary in some circles as one of the strangest weapons of the Space Race. But was this Soviet "space cannon" ever successfully fired in orbit?

What do we know?

Images of a Cold War oddity come to light

The short answer is yes, according to historian Anatoly Zak, who manages the long-running site Russian Space Web, an online hub for information about orbital pursuits in the USSR.

However, for many years, the appearance of the mysterious orbital cannon remained shrouded in mystery. In an email, Zak told Space that while the existence of this curious weapon of yesteryear had been known for decades, it was not until images were broadcast by the Russian military television program "Voennaya Priemka" that he was able to reassemble the most complete picture of how the weapon actually looked.

"This particular cannon was known since the 1990s, but that propaganda show of the Russian military TV channel showed the hardware from different directions," Zak said.

After examining this rare historical imagery, Zak said it enabled him "to build a detailed 3D reconstruction."

"This is a pretty routine method for historians and I've been doing it for more than two decades," Zak said, and images of his reconstruction, along with details about the cannon and its history, can be seen on his website.

The secret history of the Soviet Union's "space cannon"

Originally developed under weapons designer Aleksandr Nudelman for the Moscow-based KB Tochmash design bureau, inspiration for the space cannon came from aircraft gun technology designed by Aron Rikhter, builder of the famous Rikhter R-23. This gas-operated revolver automatic cannon was first developed by Rikhter in the 1950s, and adapting the weapon to the unusual demands of orbital combat led to the development of what is sometimes identified as the R-23M Kartech.

Details about the precise specifications of this orbital variant of Rikhter's famous weapon vary. In some historical accounts, the weapon is described as a modified 23-millimeter cannon, although according to Zak, it was a 14.5-millimeter cannon developed by Nudelman and his team. Estimates for its firing rate vary anywhere from 950 to several thousand rounds per minute, with some sources claiming the weapon could fire shells at a velocity of 1,500 miles per hour.

Engineers who worked with the Almaz project later claimed that during ground tests, Nudelman's orbital version of the famous Rikhter autocannon successfully pierced a metal target (a gasoline canister was reportedly used for this) from a mile away — a clear demonstration of the weapon's capabilities.

a large metal cylinder displayed in a museum

A mock-up of an Almaz space station module on display at the Exhibition of Achievements of National Economy in Moscow, Russia. (Image credit: Pulix11/Wikimedia Commons/CC BY-SA 4.0)

Firing an autocannon in orbit

Despite the successful ground tests, taking technology like this to orbit presented unique new problems for the Almaz project team.

As opposed to mounting the weapon on a turret, it was reportedly attached directly to the Almaz station itself. In this way, cosmonauts were able to use an optical sight for aiming, although this also required the entire 20-ton space station to be oriented toward the intended target—in essence, the entire station served as a massive orbital gun mount.

The Almaz program was concealed behind the Soviet Union's more widely known Salyut space station program. Although presented publicly as civilian technologies, some of the Salyut spacecraft were secretly developed and deployed as reconnaissance platforms equipped with state-of-the-art cameras and other intelligence collection utilities. In 1974, it was aboard one of these "civilian" spacecraft — Salyut 3 — that the cannon was carried to orbit.

Based on the available historical information, the weapon is believed to have only been fired in space on one occasion, which took place on Jan. 24, 1975. At this time, Salyut 3's crew had already returned to Earth, and the station was scheduled for deliberate deorbiting within hours of the planned test of the weapon.

One obvious reason for this had been that officials weren't entirely certain what the effects of firing the cannon might be on the spacecraft, such as the weapon's recoil on the station while fired in a microgravity environment. To overcome this, the station's maneuvering thrusters were reportedly fired at the time the weapon was fired in order to overcome problems resulting from recoil.

Here again, accounts differ, although an estimated 20 rounds were fired during the test, either at once or in a series of bursts. Each of the projectiles subsequently entered Earth's atmosphere and is believed to have burned up during reentry.

two metal cylinders joined at their ends, on a black background

The Soviet Union's Salyut 6 space station (at left) is seen docked with the Soyuz T-4 spacecraft in 1981. (Image credit: Rosccosmos)

What remains unknown?

Today, it remains unclear what, if anything, the Soviet engineers learned during these tests. No detailed results of the experiment were ever released — at least not publicly.

Altogether, it seems likely that Soviet officials considered the weapon impractical, and plans for later Soviet space stations reportedly looked at the use of interceptor missiles as their primary means of defense.

Meanwhile, the Soviet military was steadily embracing more efficient orbital technologies: uncrewed reconnaissance satellites. The appeal of using low-cost satellites for reconnaissance won out in the end, and an upgraded version of the Almaz station, which had initially been slated for launch later that decade, never made its way to orbit.

The mystery continues

Arguably, the story represents one of the more unusual chapters in Cold War military experimentation, and while many details remain obscured in the shadows of Cold War-era Soviet history, enough is known today to confirm that the Almaz project's tests represent the only known case where a conventional firearm was deliberately fired in orbit.

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Is there a hidden ‘Planet 9’ in our solar system?

For more than a century, astronomers have been captivated by the idea that an undiscovered planet could be lurking in the furthest reaches of our solar system.

The search for this elusive, hypothetical planet has taken many forms over the decades. The discovery of Neptune in 1846 demonstrated that an unseen planet might be inferred from its gravitational effects on other worlds. Based on this, the search for a ninth planet began in earnest, seemingly culminating with the discovery of Pluto by astronomer Clyde W. Tombaugh in 1930.

However, decades later in August 2006, Pluto's long-held planetary status was withdrawn after its formal reclassification as a dwarf planet, launching a debate over the Kuiper Belt object's identity that continues today. Yet beyond the controversy over how Pluto should be classified, the quest to determine whether a hidden ninth planet may exist in our solar system continues — and some astronomers are more confident than ever that its discovery could be imminent.

What do we know?

The story of our solar system's unconfirmed ninth planet takes us back to the early decades of the last century. At that time, astronomers began to suspect that, much like Neptune's discovery based on irregularities in the motion of Uranus, evidence of even more distant planets might begin to surface through similar observations. This prompted American astronomer Percival Lowell to advance the idea that orbital irregularities displayed by both Uranus and Neptune could point to the existence of a distant, unknown planet — one he dubbed "Planet X."

Today, although Lowell's name for this hypothetical planet is sometimes used interchangeably with the idea of a "Planet Nine," the concepts are slightly different. While the early search for Planet X relied on observations of the motion of Uranus and Neptune, new data that included Voyager 2's encounters with those planets in the 1980s helped reveal that their orbital behavior could be explained without the introduction of an unknown ninth planet.

By contrast, modern proponents of the existence of a ninth planet focus their searches further out, looking instead to orbital peculiarities in smaller objects that occupy the distant reaches of the solar system. This approach to solving the Planet Nine mystery was put forward in 2016 by Caltech astronomers Konstantin Batygin and Michael Brown, who argued that an undiscovered planet could account for the odd orbital patterns displayed by several extreme trans-Neptunian objects in the distant solar system.

a blue orb on a black, starry background

An illustration of the hypothesized Planet Nine. (Image credit: Mark Garlick/Science Photo Library/Getty Images)

What remains unknown?

In 2024, the Caltech team presented additional findings, which specifically focused on long-period, low-inclination objects that are known to traverse Neptune's orbit.

"These objects are dynamically unstable, so the population has to be continuously replenished," Batygin recently told Space in an email. "In our 2024 work, we found that Planet Nine naturally produces the observed population, whereas the model without Planet Nine is strongly inconsistent with the data once observational biases are accounted for."

According to Batygin, the Planet Nine theory can potentially explain several unusual attributes about the distant solar system, which include the phenomena of orbital clustering, large perihelion distances some objects exhibit, the presence of retrograde bodies, and objects with highly inclined orbits (meaning their orbital paths are tilted at large angles).

Right now, Batygin says the only thing still lacking from the growing body of evidence is a direct detection of Planet Nine itself. Still, while he concedes that such direct detections remain elusive, he also maintains that something must account for the current data he, Brown, and others have collected.

"If the observed dynamical structure is real," Batygin told Space, "there is presently no comparably compelling alternative theoretical explanation."

The existence of a roughly Neptune-mass Planet Nine could explain why the few known extreme trans-Neptunian objects seem to be clustered together in space. The diagram was created using WorldWide Telescope. (Image credit: Caltech/R. Hurt (IPAC))

The mystery continues

Fortunately, powerful facilities like the Vera C. Rubin Observatory in Chile could soon provide the observations currently missing from the body of data needed to support the existence of a ninth planet.

In the meantime, some promising additional discoveries have been made in recent years, which could help to strengthen the statistical case for things like orbital clustering being related to an undiscovered object at the edge of the solar system.

However, Batygin advises that astronomers should be cautious in interpreting such findings.

"I would say the picture has become more complicated, rather than simply stronger or weaker," Batygin told Space. "One has to be careful about quoting a single significance for 'clustering,' because the theory does not predict that every distant object should be clustered."

As far as what would offer the clearest support for Planet Nine's existence — short of obtaining direct visual confirmation — Batygin says ongoing discoveries of distant objects in the solar system, and the patterns that emerge in their behavior, could provide the most promising new data.

"For me, the clearest non-imaging evidence would be for the dynamical patterns in the outer solar system to sharpen dramatically as the sample grows," Batygin told Space, noting that this would particularly be the case "if several independent observables converge on the same Planet Nine parameters."

"If a much larger, well-characterized sample simultaneously exhibited the predicted apsidal structure, orbital-plane structure, perihelion distribution, inclination distribution, and Neptune-crossing population, it would become very difficult to explain the observations without a common gravitational perturber," Batygin says.

With an ever-growing number of powerful ground and space-based observatories going into service, it could be just a matter of time before we receive the final confirmation that a ninth planet has been lurking out there—or that another explanation can be proven to account for its apparent gravitational fingerprints.

Until then, the search for Planet Nine remains much like what "Planet X" was more than a century ago: a captivating idea awaiting a breakthrough observation — one that could lead to a major discovery that significantly expands our knowledge of the solar system.

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The Vela Incident: Did an American satellite detect a secret nuclear test in 1979?

It began with an unusual flash detected off the coast of South Africa by an aging American satellite — and to this day, debate continues over whether this odd Cold War event involved an illicit atmospheric nuclear test.

The strange story of the "South Atlantic Flash," better known as the Vela Incident, began on Sept. 22, 1979. At that time, Vela 6911, a satellite in a constellation developed by the United States for the specific purpose of detecting nuclear detonations, observed something that immediately alarmed officials: a peculiar flash of light emanating from somewhere over the South Atlantic Ocean.

A significant part of what concerned U.S. officials at the time had been the double flash of light detected during the event — a distinctive feature that strongly resembled the flashes produced by a nuclear explosion in Earth's atmosphere. The characteristic double flash results from the rapidly changing brightness of the fireball and shock wave produced by an atmospheric nuclear detonation, creating a distinctive optical signature that Vela's sensors were specifically designed to recognize. The South Atlantic event, therefore, seemed like a prime candidate for a secretive nuclear test being carried out by an unknown party — but if that were the case, who was responsible?

What do we know?

U.S. officials responded to a possible nuclear test

Then-President Jimmy Carter was promptly alerted to the situation, as evidenced in diaries the former U.S. leader would publish years later. "There was indication of a nuclear explosion in the region of South Africa," Carter wrote in an entry on the same date of the event. A later entry penned the following February would go on to add that "We have a growing belief among our scientists that the Israelis did indeed conduct a nuclear test explosion in the ocean near the southern end of Africa."

a man in a suit sits at a large wooden desk beside a globe

President Jimmy Carter, seated at a desk in the Oval Office of the White House in 1980. (Image credit: Bettmann/Getty Images)

Despite that belief regarding the possibility of a clandestine nuclear test, a scientific panel assembled in 1980, chaired by MIT professor Jack Ruina, eventually put forward an alternative explanation: that the flash had more likely been an anomaly caused by a small meteoroid striking the satellite.

Notably, the panel did not rule out the possibility of a nuclear explosion at the time, although the alternative they put forward remained controversial among scientists and intelligence officials.

a memorandum on white house stationary

A memorandum to Director of Central Intelligence Stansfield Turner from Frank Press, White House science adviser, in which Press explains the reasoning behind the Ruina panel's conclusion that the Vela flash was "probably not from a nuclear explosion" and was therefore more likely "caused by a natural event." (Image credit: Public Domain/National Security Archive)

Documents and government insiders surface

By the turn of the 21st century, formerly classified documents began to surface that revealed the extent of the inner tensions between U.S. government agencies over what caused the Vela incident.

Among the critics of the debris-induced "anomaly" hypothesis had been Defense Intelligence Agency Vice Director Jack Varona. According to documents released in 2006, Varona said the investigations by the 1980 scientific panel had been a politically motivated "whitewash," and that evidence collected by the U.S. intelligence community included detections "unique to nuclear shots in a maritime environment," based on an analysis by the Naval Research Laboratory.

Varona wasn't alone. Other former intelligence officials who came forward over the years included Stansfield Turner, the former Director of Central Intelligence during the Carter administration, who in 2003 described the Vela detection as a "man-made phenomenon."

Similar views were advanced by retired CIA officer Tyler Drumheller, who in 2006 wrote that he had sources at the time who "collectively provided incontrovertible evidence that the [South African] apartheid government had in fact tested a nuclear bomb in the South Atlantic in 1979, and that they had developed a delivery system with assistance from the Israelis."

a dodecahedron-shaped satellite in a clean room; and an illustration of the same satellite in orbit above earth

The Vela-5A & B satellites in a cleanroom at Los Alamos National Laboratory (left); and an illustration of one of the satellites in orbit above Earth (right). (Image credit: Los Alamos National Laboratory)

What remains unknown?

Scientists revisit the mystery

While we still don't know if the South Atlantic Flash was a nuclear test, several scientists have reexamined the available evidence within the last decade, and what they found has lent further weight to the idea that the Vela incident had involved a detonation of some kind.

Among the most significant assessments, a 2017 study by Christopher Wright and Lars-Erik De Geer combined modern research into interplanetary dust and hypervelocity impacts with revelations from recently declassified documents, as well as publicly available information that had been previously overlooked.

Their conclusion: while no model was presented for the tenuous "meteoroid" theory advanced by the May 1980 scientific panel, the double flash observed by the Vela satellite in 1979 was indeed "consistent with a nuclear explosion, albeit detected by an aged satellite for which background modulation was abnormal and/or commenced earlier," adding that additional radionuclide and hydroacoustic evidence existed which supported the conclusion "that the Vela Incident was a nuclear weapon test explosion."

Wright and De Geer weren't alone either. A 2022 study examined data collected by NASA's Nimbus-7 satellite just 16 minutes and 44 seconds after the double flash over the South Atlantic, which suggested a disturbance in the ozone layer that appeared to be consistent with a blast-generated shock wave.

an illustration of a hexagonal satellite with two wing-like solar panels in orbit above earth

Artist's concept of a Nimbus spacecraft in orbit over Earth. (Image credit: NASA)

Still, some of the original members of the 1980 scientific panel have defended its work amid the more recent scientific studies. Richard Mueller, who served as the panel's youngest member at the time, defended the group's conclusions in a November 2019 oral history conference, maintaining that the chances the Vela incident had involved a nuclear event were "as close to zero as it gets."

This determination, Mueller argued, was made despite early interpretations by many panelists that a nuclear event had seemed most likely. Wright and De Geer, both of whom attended the 2019 oral history conference, were among the participants that pushed back on Mueller's views.

Who was responsible?

Amid the mounting evidence over the last several decades suggesting the Vela incident was indeed a nuclear test, debate continues over who was most likely to have been responsible.

Although suspicions have long centered on a cooperative — and secret — strategic effort between apartheid-era South Africa and Israel, publicly available evidence remains lacking, and a fair amount of information in declassified documents that could point to this possibility remains redacted.

a dodecahedron-shaped satellite in orbit above earth

An illustration of two Vela satellites separating in orbit. (Image credit: Los Alamos National Laboratory)

The mystery remains

Thus, after more than four decades, questions continue to linger over the famous Vela incident, including what nations might have been involved in such a test if it occurred. Despite that uncertainty, one thing does seem evident: information conveyed in unredacted portions of declassified records, combined with modern scientific analyses, increasingly point to the likelihood that the strange "South Atlantic Flash" in 1979 was anything but natural.