Siberia’s Tungsuka Event, the unexplainable explosion 1000 times greater than an atomic bomb

‘It was like the sky opened up and split in half. I put my hands in front of my eyes and I could see the bones in my hands.’

The name of the Evenki tribeswoman—who thus described the enormous explosion that rattled the earth and tore the sky asunder above Vanavara in Siberia shortly after dawn on 20 July 1908—was never recorded. Nor was her ultimate fate. Although she must have survived long enough to be talking 20 years after the strange event happened. Because we know no one was asking the Evenki about it before then.

Two decades on, when scientists finally arrived in this remote corner of Russian Siberia to collect eyewitness accounts, surviving members of this nomadic reindeer-herding tribe told of a terrible day that literally shook their world. A day that still has a profound influence on the way they view that corner of Tunguska, several generations since it was set ablaze by an explosion believed to have measured 15 megaton—1000 times bigger then the atomic blast that levelled Hiroshima at the end of World War II.

Such was the fury of the fireball, that the Evenki became convinced they were being punished by a deity called Ogdy—god of thunder. Their shaman forbade them to go anywhere near the site of the explosion ever again. As if they needed telling.

The people closest to ground zero were an estimated 20 miles from the blast site. Many were asleep in their tents, but not for long. The explosion blew them into the air and left some unconscious. At least one man was slammed into a tree with fatal force.

Other reports talk of an immense firestorm, unleashing a tsunami of death and destruction that swept across the remote land, vaporising people and their reindeer. Afterwards a veil of fog and thick smoke from a million burning trees descended. The smog has cleared—of course—in the intervening century, but the causes of the event remain surprisingly hazy, even today.

According to Russia, there were no reported human casualties, something that is explained fairly easily by the fact that no officials or investigators from Russia visited the site for nearly 20 years after the incident.

However, the voices of the Evenki survivors, when they were finally recorded by Russian mineralogist Leonid Kulik—the first person to investigate the ultra remote scene of the explosiontell a very different tale.

Downed trees lay everywhere, a fraction of aftermath of the 1908 Tunguska event
Downed trees lay everywhere, a fraction of aftermath of the 1908 Tunguska Event

‘There was thunder,’ said one. ‘The earth began to move and rock.’

‘I saw the sky split in two,’ recalled another. ‘Fire appeared high and wide around us.’

‘It became dazzling bright,’ a third told Kulik. ‘As if there was a second sun in the sky.’

One thing is certain—they weren’t making it up. Shockwaves rolled right around the planet that day. Twice. Seismic measuring devices in cities all over world picked it up. Windows broke and people standing 60 kilometres from the explosion were rudely flung to the ground. Observers 170 kilometres from the blast saw something sunlike in the cloudless sky, and ‘deafening bangs’ were heard 500 kilometres away.

In Edwardian London, newspapers reported luminous clouds appearing in the night sky—providing enough light to play tennis in the middle of the night. There was temporary talk of a midnight sun. Russian publications reported it too—briefly. And then it was forgotten. But not by the Evenki.

Almost two decades later, inspired by a serendipitous note left on a calendar and his own innate and insatiable scientific curiosity, Leonid Kulik set off to see what had really happened around the Podkamennaya Tunguska River on that mysterious morning.

A former soldier—who had seen action in the Russo-Japanese War and World War I, and spent a spell in jail for revolutionary activities in between—Kulik was not a man to be put off by distance or discomfort. It took him some time, but eventually he found an Evenki man willing to guide him along rivers and across icy swamps, to the edge of the site. But no further; the instructions of the shaman still prevented the tribespeople from going too close. Kulik pushed on, alone, aside from a million mosquitoes, and on foot.

In the small column inches they had dedicated to it, contemporary Russian reports referred to the explosion as a meteorite impact, and Kulik came towards the site carrying the same assumption. What he discovered confounded and confused him, and continues to have the same effect on the world’s scientific community today.

Although, actually, it’s what he didn’t find (and what no one else has been able to locate since either) that causes the majority of the head scratching. Because there was no crater, no indication that a meteorite had hit the ground at all. Considering this event is now regarded as the largest impact to have slammed into Planet Earth in living memory, this is an epic enigma.

And the site had more surprises in stock too. Across 2000 square kilometres, some 80 million trees had been decked—knocked to the ground in an enormous outward spreading pattern, shaped a little like a butterfly’s wings. But at ground zero, in the very middle of this ring of devastation, not only was there no crater, but a copse of tree corpses remained standing, albeit with all their limbs ripped off.

Kulik didn’t discover all this on his low-budget 1927 reconnaissance trip, of course. The shape made by the flattened trees was revealed during an aerial survey carried out in 1938, and Kulik returned to make three subsequent forays to the felled forests of Tunguska, later tooled up with all the research equipment and surveying gear the Soviet machine could muster.

The Russians had decided that the tenacious mineralogist’s mission was the perfect plot for a story about proletarian-led scientific endeavour, and they got right behind it. However, two events in World War II would change everything.

The first was the death of Kulik, who despite his age (late 50s) had volunteered for service, was captured by the Germans and died of typhus in a POW camp. The second was the detonation of atomic bombs over Hiroshima and Nagasaki in Japan.

Photo from an aerial survey of the Tunguska region, 1938 (thirty years after the event). Courtesy of the Tunguska Page, Bologna University.
Photo from an aerial survey of the Tunguska region, 1938 (thirty years after the event). Courtesy of the Tunguska Page, Bologna University.

When the awful effect of the nuclear explosion in Hiroshima was relayed in detail to a shell-shocked world—including descriptions of how some buildings directly beneath the blast remained standing while the rest of the city was levelled—the hairs on the ears of Soviet scientists stood to attention. Suddenly they radically altered their approach to the Tunguska site, launching an urgent search for signs of radioactivity (limited traces of which were indeed found, with cell mutation and damage reported in plants and some humans) and even extra terrestrial matter.

Various reports claim that, once radioactive objects were discovered, the entire area was locked down by the KGB. Everything ever taken from site was collected, and was either destroyed or disappeared into the bowels of Soviet buildings somewhere very secret. Scientists and locals were allegedly told to either stay silent about it, or refer to the event only as a meteorite collision. The message was clear: nothing to see here.

Inevitably, such a strong-arm approach only increased speculation and conspiracy theories began running rampant. The Space Race would soon be kicked off in earnest, with the launch of Sputnik I, and during an era when alien activity was fast becoming an international obsession, the event quickly became the Russian Roswell.

Former Soviet army colonel turned writer, Alexander Kazantsev, wrote several books about Tunguska, based on conjecture that the blast was caused by a nuclear-powered spaceship exploding just above earth. Predictably, these proved popular, but this wasn’t even the most left-field theory to do the rounds.

Blame for the blast has even been levelled at the eccentric genius Nikola Tesla, conceiver of the modern alternating current (AC) electricity supply system, who is known to have been working on a so-called Death Ray design from his Wardenclyffe lair in New York at the time.

Also called the ‘Peace Ray’, because of its potential to stop traditional warfare, this particle-accelerator style weapon of mass destruction could, theoretically, beam a concentrated payload of electricity through the atmosphere, to hit a predetermined target with devastating force.

According to Tesla, his ray gun would: ‘Send particles through the free air, of such tremendous energy that they will bring down a fleet of 10,000 enemy airplanes at a distance of 200 miles from a defending nation’s border and will cause armies to drop dead in their tracks.’

Recently spurned by sponsors because of his egalitarian ideas about empowering the masses with free electricity (delivered wirelessly, no less), Tesla embarked—it’s claimed—on an audacious stunt to demonstrate his awesome invention by staging a light show intended primarily for an audience of one: Robert Peary, an influential American explorer who in 1908 was making his second attempt to reach the North Pole. Proponents of this theory claim that Telsa made an error in his calculations, and the Evenki of Tunguska paid a terrible price for it.

On the face of it, this rather far-fetched theory reads like a discarded plot idea for Despicable Me III, but the fact that Tesla truly was a mercurial genius is beyond doubt, and he was certainly serious about his invention—having approached several governments about its use. ‘It is not an experiment,’ he said during an event dedicated to the concept in 1937. ‘I have built, demonstrated and used it.’

When he died, the FBI raided the hotel room he’d been occupying, to seize all the scientist’s notes and materials, which were subsequently buried beyond prying eyes; all of which has fuelled the fantastical flames.

More recently, modern researchers—including astrophysicist Wolfgang Kundt from the University of Bonn in Germany—have argued that the event was caused by an eruption of gas from kimberlitic caverns below, and had nothing to do with a bolt from the heavens above.

‘It would have come from the molten earth, some 3,000 kilometres deep,’ Kundt has said. ‘The natural gas would be stored as a fluid that deep, and when it reaches the surface it would become a gas and expand by a factor of thousand in volume, for a huge explosion.’

Similar theories have been put forward to explain another Siberian enigma, the Patomskiy Crater, a truly bizarre formation of shattered limestone in the Irkutsk region—which has an extra layer of intrigue, because it continues to move and evolve. When it was first discovered in 1949, some scientists attempted to link Patomskiy with the Tunguska explosion, but later tests have shown that the crater was created a couple of hundred years before the 1908 blast.

The Patomskiy Crater
The Patomskiy Crater

To date, unless you agree with the Evenki faithful and accept the Thunder God theory, or side with the ufologists, minions and mad-professor groupies, the most enduring and prosaically plausible explanation for Tunguska event is that it was caused by a meteorite. Although this in itself is far from simple, and intense debate still rages over what exactly invaded Siberia from space on that dramatic day, when one of the 20th century’s greatest mysteries was born.

The lack of a crater complicates the cosmic impact idea, but scientists generally accept that it was caused by either an asteroid (another term for meteorite, mostly made of metal and rock) or a comet (mainly ice) making it into Earth’s atmosphere, but exploding because of intense pressure shortly before hitting terra firma. Statistically, it was more likely to be an asteroid (there are simply more of them pinging around us) but the comet argument has its devotees too.

Whatever it was made of, scientists initially believed that such a body must have measured at least 30 metres across, packing a mass similar to a modern cruise liner, in order to inflict the degree of damage done, but estimates have now been scaled down based on information yielded by supercomputer simulations.

Arguments over such minutiae might seem somewhat pedantic, but for planetary scientist and astrobiologists at NASA’s Ames Research Center, getting to the bottom of exactly what happened on that June day in 1908, is of crucial importance for future forecasting of such events. Our planet is surrounded by small objects such as the one profiled by the computer analysis, and we might not be so lucky with the next Tunguska-style event.

German scientist Christopj Brenneisen would agree. He has pointed out that, if it was indeed a meteorite, and it had arrived a few moments later, after the Earth had rotated a little bit more, whatever caused such carnage in Siberia would have destroyed St Petersburg. Or, an hour later, Helsinki. Then Stockholm and Oslo and so on. All these cities share the same latitude as Vanavara, and if any of those scenarios had played out, everyone around the globe would know for sure what happened that day.