On June 30, 1908, at 7.17 A.M., in a remote part of Russia, a fireball swept through the daytime sky. Within moments, something exploded in the atmosphere above Siberia’s Podkamennaya Tunguska River in what is now Krasnoyarsk Krai.
The inhabitants of Central Siberia in the 300-600 mile radius saw the explosion. According to one eyewitness,
“the sky was split in two, and high above the forest the whole northern part of the sky appeared covered with fire… At that moment there was a bang in the sky and a mighty crash… The crash was followed by a noise like stones falling from the sky, or of guns firing.”
Supposedly, the fireball was 50-100 m wide. It flattened about 80 million trees and demolished wildlife in the six-to-nine mile radius. The trunks and brunches of the trees however, were not burnt, just singed on the outside, seemingly by the heat wave.
After the explosion, abnormally bright nighttimes had been reported throughout Russia’s European and Western part. People were able to read at night without any additional lighting provided.
The Tunguska event remains the most powerful explosion recorded in history. It produced about 185 times more energy than the Hiroshima atomic bomb. Seismic rumbles reached as far as the UK.
So what caused such a destructive explosion?
Back then, it was difficult to reach this remote part of Siberia. The Tunguska region is known for its long hostile winter and a very short summer, when the ground turns into a muddy uninhabitable swamp. That’s why nobody went to the site to investigate the explosion, when it happened. Moreover, the Russian authorities had more pressing concerns, as World War I and the Russian Revolution were just a few years away.
It wasn’t until 1927 that Leonid Kulik led the first Soviet research expedition to investigate the Tunguska event.
When he got there, the damage was still apparent, almost 20 years after the blast. Kulik found a large area of flattened trees, spreading out about 31 miles (50 km) wide in a weird butterfly shape.
Kulik proposed that an extraterrestrial meteor had exploded in the atmosphere. However, there was no impact crater, or in fact, any meteoric remnants at all.
Today, over 100 years after the most powerful explosion in documented history, scientists are still trying to figure out what exactly happened that day in the sky…
The reason why the Tunguska event is so dramatic is that it was an extremely rare case of what researchers call a “megaton” event – as the energy emitted was about 10-15 megatons of TNT. It is the only event of that magnitude that has happened in recent history.
Most theories suggest that an asteroid or a comet that was responsible for the blast. Russian researchers said that it was a comet, not a meteor that caused the damage. While meteorites are made up of metal and rock, comets are “dirty snowballs” of ice and dust, which can explain the absence of alien rock fragments.
Some explanations were pretty crazy such as the encounter of Earth with an alien spacecraft, a mini-black-hole, a nuclear bomb, or a particle of antimatter.
According to Dr. Artemieva of the Planetary Science Institute in Tucson, Arizona, ideas like this are produced by human psychology:
“People who like secrets and ‘theories’ usually do not listen to scientists. A huge explosion, coupled with a lack of cosmic remnants, is ripe for these kinds of speculations.”
At the turn of the 21st century, a new theory was proposed blaming the explosion on the unfortunate experiment by Nikola Tesla. It suggested that the scientist conducted a wireless energy transmission “through the air” to illuminate the way to the North Pole for the American Arctic explorer Robert Pirie. The uninhabited region between Alaska and the North Pole was a perfect practice ground for executing wireless energy transmission, but, due to the absence of proper tools, the measurements were incorrect, causing the explosion.
So… Tesla kept his experiment secret as he realized how grossly he missed the target and how much damage he had done. Scary hidden truth or another crazy theory?
In 2013, the Russian research team put a stop to the speculations. Led by Victor Kvasnytsya of the National Academy of Sciences of Ukraine, the researchers analyzed microscopic samples of rocks collected from the explosion site in 1978.
Kvasnytsya came to the following conclusion:
“Our study of samples from Tunguska, as well as research of many other authors reveals meteorite origin of Tunguska event. We believe that nothing paranormal happened at Tunguska.”
However, it is still not a definitive conclusion. Meteor showers occur often, and many small ones might therefore sprinkle their remnants onto Earth unnoticed. Samples with meteoric origin could presumably come from one of these. It is also doubtful that the peat collected dates from 1908.
We may never find out whether the Tunguska event was caused by a meteor or comet. And unfortunately, we still cannot fully protect ourselves from similar events.
Chelyabinsk-sized meteors are believed to occur roughly every 1000 years, while Tunguska style impacts as often as once every 100-200 years. If another explosion like the Tunguska event took place above a populated city, it would kill thousands if not millions…
The good news is that probability of that happening is extremely small, especially given the huge surface area of Earth that is covered in water.
Gareth Collins of Imperial College London, UK, states:
“When a Tunguska-type event happens again, the overwhelming probability is that it will happen nowhere near human population.”
And don’t forget…
Thousands of astronomers constantly peer into the skies with their telescopes to look for signs that rocks with the potential to cause a similar event are heading our way, and to assess the risk that they pose just so that we can sleep at night…