Strange Places: Tunguska

What Caused an Apocalyptic Explosion in the Siberian Wilderness Over a Century Ago?

Michael East
Oct 20, 2020 · 11 min read

It was an event that had the potential to kill millions and devastate an area the size of Rhode Island. A mysterious explosion in the Siberian wilderness that was a lucky escape for humanity, the blast unleashed a force that destroyed hundreds of miles of forest with the power of 185 Hiroshimas. While an asteroid has been blamed, there is no actual scientific consensus over what caused the destruction at Tunguska. It is a mystery that has stood for over a hundred years.

On June 30 1908, Evenki natives in the hills around Lake Baikal, Russia, watched in awe as a column of blueish white light lit up the sky. Nearly as bright as the Sun itself, the column was moving across the sky and on an impact trajectory. A little over ten minutes later there was an immense flash, and the roar of an explosion was heard, the shockwave being felt hundreds of miles away, with windows broken and people thrown off their feet.

“Peasants saw to the northwest, rather high above the horizon, some strangely bright (impossible to look at) bluish-white heavenly body, which for 10 minutes moved downwards. The body appeared as a “pipe”, i.e., a cylinder. The sky was cloudless, only a small dark cloud was observed in the general direction of the bright body. It was hot and dry. As the body neared the ground (forest), the bright body seemed to smudge, and then turned into a giant billow of black smoke, and a loud knocking (not thunder) was heard as if large stones were falling, or artillery was fired. All buildings shook. At the same time, the cloud began emitting flames of uncertain shapes. All villagers were stricken with panic and took to the streets, women cried, thinking it was the end of the world.”

Sibir, July 2, 1908

Such was the force of the blast that airwaves from the detonation were felt as far away as Washington DC and the UK. Some places were estimated to have received a wave the equivalent to an earthquake measuring 5.0 on the Richter scale. For days afterwards, the night sky across Europe and Asia was bright, photographs being taken in times of usual darkness and people were said to be able to read newspapers with ease. The Mount Wilson observatory noted that atmospheric transparency was decreased for months after the event, with dust particles filling the atmosphere.

Clearly, a significant event had transpired in the Siberian wilderness.

Fallen trees at Tunguska, 1927 | Public Domain

Despite local press reports, however, it wasn’t until the 1920s that a full scientific analysis could be carried out at Tunguska when Leonid Kulik, the chief curator for the meteorite collection of the St. Petersburg museum, led an expedition to investigate the blast in 1921. The harsh Siberian conditions forced the abandonment of this initial effort, yet what little evidence he did obtain led him to believe a meteorite impact was responsible. Kulik set about persuading the government that any potentially recovered meteoric iron would be a boost to Soviet industry. In 1927, nearly 20 years after the event, Kulik would finally lead a second team to their goal.

“At first, the locals were reluctant to tell Kulik about the event. They believed the blast was a visitation by the god Ogdy, who had cursed the area by smashing trees and killing animals.”

Don Yeomans, manager of the Near-Earth Object Office at NASA’s Jet Propulsion Laboratory.

Leonid Alekseyevich Kulik, Russian mineralogist, investigator of the Tunguska event | Public domain (enhanced by the author)

Despite some reluctance on the part of the locals, Kulik was able to obtain some accounts and hired Evenki hunters to act as trackers and guides, his party making their way to ground zero. His first attempt to reach the site once again failed as the Evenki stopped south of the site and refused to go further, being in terror of what they termed “the Valleymen” who lurked in the location. Returning a second time with new guides, however, the party discovered 800 square miles of forest devastated, trees radially laying on their sides out from the point of impact. The pattern was later determined to be butterfly-shaped. While there was no evidence anyone had been killed by the blast, hundreds of reindeer had perished. The tree pattern, however, acted as a guide toward the centre of the explosion and what they found astonished Kulik.

There was no impact crater. Instead, the investigators found trees standing upright stripped of their branches and foliage, appearing as if a forest of telephone masts or flag poles. This zone was almost five miles across. The phenomenon requires shockwaves moving at incredible speeds, the branches being broken off before they can transfer the momentum of the impact to the trunk. It is a phenomena would be noted again after the atomic bombing of Hiroshima.

Photograph from Kulik’s 1929 expedition taken near the Hushmo River | Public Domain

Over the next decade, Kulik would lead three more expeditions to Tunguska. He believed he may have discovered impact craters, yet later dismissed his findings after finding a tree stump at the bottom of one of the bogs. He would also organise aerial photography, providing many of the famous lasting images of the events. During later treks to ground zero, the locals began to open up more to him. One account that Kulik managed to obtain was that of Sergei Semenov who was based at the Vanara trading post. In the statement, Semenov noted that “the sky [had] split in two and fire appeared high and wide over the forest”.

“The split in the sky grew larger, and the entire northern side was covered with fire. At that moment I became so hot that I couldn’t bear it as if my shirt was on fire; from the northern side, where the fire was, came strong heat. I wanted to tear off my shirt and throw it down, but then the sky shut closed, and a strong thump sounded, and I was thrown a few metres. I lost my senses for a moment, but then my wife ran out and led me to the house. After that such noise came, as if rocks were falling or cannons were firing, the Earth shook, and when I was on the ground, I pressed my head down, fearing rocks would smash it. When the sky opened up, hot wind raced between the houses, like from cannons, which left traces in the ground like pathways, and it damaged some crops. Later we saw that many windows were shattered, and in the barn, a part of the iron lock snapped.”

Sergei Semenov, as recorded by Leonid Kulik.

Later analysis at the site revealed microscopic silicate and magnetite spheres in the trees and soil and chemical analysis showed they had high concentrations of nickel relative to iron as found in meteorites. The distribution of the spheres was consistent with a detonation in the air as opposed to on the ground. An airburst.

“A century later some still debate the cause and come up with different scenarios that could have caused the explosion, but the generally agreed upon theory is that on the morning of June 30, 1908, a large space rock, about 120 feet across, entered the atmosphere of Siberia and then detonated in the sky.”

Don Yeomans, manager of the Near-Earth Object Office at NASA’s Jet Propulsion Laboratory.

The eminent British astronomer FJW Whipple suggested in the 1930s that the details surrounding the Tunguska event suggested the impact of a small comet, explaining the dust particles in the atmosphere and lack of impact crater. Whipple believed that the comet was vaporised by contact with the atmosphere.

The theory became generally accepted in the scientific community, with the Slovak astronomer Ľubor Kresák believing the culprit to have been a shard of Encke’s Comet which completes an orbit of the Sun every 3.3 years. The comet is responsible for the annual Beta Taurids meteor shower, and the location of the event in Tunguska is consistent with what would be expected from any fragment breaking off from Encke’s comet.

However, the comet theory has several issues, primarily being that any fragment should have disintegrated long before the air burst at 28,000 feet. A 2001 study utilised orbital modelling to conclude there was an 83% chance that the Tunguska object moved on an asteroidal path from the asteroid belt and only a 17% chance of the item being on a cometary trajectory.

“When the first modern models for atmospheric impacts were published in 1993, it became clear that this was a stony body… somewhere between an ordinary chondrite and a carbonaceous chondrite in physical properties… In contrast, cometary objects with this mass, of low density and/or icy composition, would explode tens of kilometres above the surface and cause no harm.”

David Morrison, NASA Asteroid expert.

It is now believed by most scientists that it was indeed an asteroid that entered the Earth’s atmosphere. Weighing 220-million-pounds and travelling at 33,500 miles per hour, the rapidly descending rock caused the surrounding atmosphere to heat 44,500 degrees Fahrenheit. The lack of impact crater, as would typically be expected, is explained by a combined pressure and heat causing fragmentation over Tunguska, the asteroid producing a fireball in the air that was equal to 185 atomic bombs. However, not a single piece of such rock has ever been found, even microscopic.

“If the Tunguska event was in fact caused by a comet, it would be a unique occurrence rather than an important case study of a known class of phenomena. On the other hand, if an asteroid did explode in the Siberian skies that June morning, why has no-one yet found fragments?”

Luca Gasperini, an Italian researcher.

The debate between those who believe the object was a comet and those who think it was an asteroid still rage, with dissenting voices raised over the explosion being neither one.

The astrophysicist Wolfgang Kundt has suggested that the detonation at Tunguska wasn’t an astral event at all. Instead, it was caused by the release and subsequent ignition of 10-million tonnes of natural gas from the Earth’s crust. A Physicist at Germany’s Bonn University, Kundt compares the Tunguska event to a similar massive release and explosion at Blake Ridge on the seabed off Norway, a “pockmark” of 280 sq. miles. Speaking alongside Kundt in 2002, Andrei Ol’khovatov, formerly of the Soviet Radio Instrument Industry Research Institute, said that the blast was caused by a “strong coupling between subterranean and meteorological phenomena” and that science is not ready to understand exactly what transpired.

The scientific uncertainty over Tunguska has led to the prevalence of the belief that extraterrestrial activity is to blame for the explosion. This theory was made ever more popular by the American science-fiction series The X-Files where events at Tunguska were central to the ongoing alien “black oil” storyline.

Alexander Kazantsev | Public Domain

While The X-Files might be said to have put the event into Western public minds as part of UFOlogy, the links between aliens and Tunguska goes back to Soviet science-fiction writer Alexander Kazantsev, who believed the event to be extraterrestrial in origin. In his novel Burning Island (1939–1940), Kazantsev suggests Tunguska as the crash site of an alien spacecraft which results in the discovery of radium-delta, the fuel to the ship. He would write extensively surrounding the subject including in his 1946 short story A Visitor From Outer Space. This tale tells of how a Martian spaceship, fuelled by nuclear power, explodes near Lake Baikal when it seeks fresh water. The Explosion meanwhile speculates again that the blast was the result of an alien craft. This story contains the additional new idea that this craft may have fired to “save the Earth from an imminent threat”. During the 1980s some Soviet scientists even backed his claims, claiming to have found evidence but never producing it.

Several other expeditions to find evidence that an alien spacecraft crashed at Tunguska have been made over the years, with one such team claiming to have foung debris of the alleged craft in 2004. Reports in the press suggested that what was found was a “technical device” and “a large block made with metal.”

The scientific response to the alleged findings was derisory.

“The Russian team stupidly stated long before they went to Siberia that the main intention of their expedition was to find the remnants of an ‘alien spaceship!’ And bingo! A week later, that’s what they claim to have found. It’s a rather sad comment on the current state of the anything-goes attitudes among some ‘science’ correspondents that such blatant rubbish is being reported — without the slightest hint of scepticism”

Benny Peiser, a researcher at Liverpool John Moores University.

If the expedition had discovered anything, it was likely to be human in origin, with the desolate Tunguska region being a drop zone for discarded rocket stages launched from Russia’s Baikonur base in Kazakhstan. The Dutch space historian Geert Sassen suggests “they might have found some parts of the fifth Vostok test flight.”

Expedition leader Yuri Lavbin, however, is adamant that what he found was not part of the Vostok flight, claiming to have found “strange quartz crystals” at ground zero with diagrams etched on them. Also, he claims to have seen black quartz stones in the shapes of cubes, five feet on each side. He believes that a UFO destroyed an asteroid to save the Earth from armageddon, the idea initially proposed by Alexander Kazantsev.

“We don’t have any technologies that can print such kind of drawings on crystals. We also found ferrum silicate that can not be produced anywhere, except in space.”

Yuri Lavbin.

Science Fiction explanations for the event have spread through popular culture. The Doctor Who novel Birthright explains the explosion as a dimensional rift, while the Star Trek novel Prime Directive prefers Vulcan involvement. Extraterrestrial origins are given in Indiana Jones and the Kingdom of the Crystal Skull while 1984’s Ghostbusters picked an interdimensional cross-rip. The Assassin’s Creed series of video games blame Nicola Tesla, while the event was the primary focus of Secret Files: Tunguska, a 2006 point and click adventure.

There are hundreds of explanations for what happened at Tunguska. They range from those that are pure fiction to those that remain in the realms of scientific possibility. While the debate may still rage, the fact remains that a devastating event happened in the Siberian wilderness in 1908, one that humanity was lucky to escape unscathed. Potential extinction and mass casualty events are at every turn, from killer diseases to disaster from above, society is more fragile than we arrogantly believe. Tunguska should serve as a warning of the dangers that we face and the real power of a universe in which we are no more significant than the particles of dust left in the wake of whatever devastated Tunguska.

I am a freelance long-form writer who writes on true crime, politics, history and more. I am entirely self-funded and if you liked this article, please consider a donation via Patreon as a token of appreciation or directly via PayPal. You can join my mailing list for the latest articles and also like my Facebook page. I’m also active on Twitter. I can be contacted for projects through my website where you’ll also find lots more content.

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Michael East

Written by

Freelance writer. Writing on true crime, mysteries, politics, history, and more. |

The Mystery Box

A publication about unsolved mysteries from the deep ocean to space and from antiquity to present day.

Michael East

Written by

Freelance writer. Writing on true crime, mysteries, politics, history, and more. |

The Mystery Box

A publication about unsolved mysteries from the deep ocean to space and from antiquity to present day.

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