Unidentified Exploding Object

06 30 tunguskaToday is the anniversary of what is known as the Tunguska Event. It is named for the Tunguska river in a very remote area of Siberia. On June 30th 1908, it was the site of a massive explosion. The blast destroyed 830 square miles (2,150 sq km) of forest. It is the largest such event in recorded history and, even now, no one can really agree on what caused it. Luckily it was such a sparsely populated area that no fatalities were reported, and hopefully this is because there weren’t any.

Because it happened in such an isolated place, and because Russia was facing a period of extreme political upheaval at the time, no one visited the area to investigate the cause until 1921. There are a few eyewitness reports of the event. This is what a man named Semyon Borisovich Semyonov had to say when he was interviewed in 1930:

“…the sky 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.”

Among those who witnessed the event, a few said they had seen an object in the sky, To some it was a red fiery ball, to others it seemed to be shaped like a tube and was blue or white in colour. Many agreed that it was too bright to look at. Most people just heard it and described a noise like thunder, or like artillery fire, or falling rocks. The tremors were recorded all over the world. For three days afterwards, glowing clouds were seen in the night sky, so bright that it was possible to read a newspaper, all over Northern Europe. The name for clouds that glow in a dark sky is ‘Noctilucent Clouds’, which is lovely. Here is a picture of some…

06 30 noctilucent clouds

The explosion is thought to have been caused either by an exploding meteorite or a comet. Leonid Kulik, the first man to investigate the site, expected to find a huge crater in the middle of the area of devastation, but what he found was a clump of trees that were stripped bare but still standing. For miles around the trees had been knocked down in a direction away from the blast. It seems that what ever caused it had exploded in the air, stripping the trees directly below it, with the force radiating outwards when it hit the ground.

Some mineral samples taken in the area suggest a meteorite, but it is far from conclusive. The lack of any obvious impact sites and the reports of glowing clouds suggest a comet. The glow could have been caused by fragments of dust and ice from the comet in the upper atmosphere catching the sun’s rays. I did find an eyewitness report that claimed a new lake had been formed in the explosion, and that it boiled for two days. But this seems to have been dismissed. However, there is a lake nearby called Lake Cheko which may or may not have been created by a fragment of meteorite. A team of investigators from the University of Bologna believe they have identified a large rock, deep in the lake which may be a piece of the meteorite. They also have evidence from the sediment in the lake that it may be only a hundred years old, but because the area is far from any centre of population, nobody can be certain how long it’s been there.

There are many other explanations on offer. Some suggest that a cloud of natural gas, from under the earth’s crust, may have been forced to the surface and then been ignited by lightening. Others that it was caused by a scientist called Nikola Tesla, who claimed to have invented, and therefore perhaps tested, a weapon that could transmit electricity through the air. Among some of the even crazier theories are a black hole colliding with the earth, an exploding spaceship and a nuclear bomb that somehow travelled back in time and exploded over Siberia. What ever happened, we are incredibly lucky that it did not explode over a major city. St Petersburg, Helsinki, Stockholm and Oslo are all on the same latitude, and could easily have been in the path of a comet, meteorite, spaceship or time-travelling bomb.

Throbbed like a Wounded Snake

06 18 moonOn the 18th June 1178, in Canterbury, just after sunset, five monks were gazing up at the moon when something very unusual happened. No one knows what is was, but it looked like this…

“There was a bright new moon, and as usual in that phase, its horns were tilted toward the east; and suddenly the upper horn split in two. From the midpoint of this division a flaming torch sprang up, spewing out, over a considerable distance, fire, hot coals, and sparks. Meanwhile the body of the moon which was below writhed, as it were, in anxiety, and, to put it in the words of those who reported it to me and saw it with their own eyes, the moon throbbed like a wounded snake. Afterwards it resumed its proper state. This phenomenon was repeated a dozen times or more, the flame assuming various twisting shapes at random and then returning to normal. Then after these transformations the moon from horn to horn, that is along its whole length, took on a blackish appearance.”

We know this because it was written down by a chronicler called Gervase of Canterbury. He had the story directly from the eyewitnesses. It must have looked as though the world was about to end. They must have been terrified. Sadly, as it happened more than eight hundred years ago, we can only guess at what really happened. There are a couple of theories though.

In 1978, a geologist called Jack B Hartung published an article suggesting that what the monks had witnessed was a comet or asteroid colliding with the Moon forming the 14 mile wide crater on the far side of the moon, now called the Giordano Bruno Crater. I mentioned Bruno only a few of days ago. A man whose entire body of work was banned by the Catholic Church between 1600 and 1966. Yet in 1961, he had a crater named after him. Which just goes to show, you can’t please all of the people all of the time.

06 18 giordano bruno craterThe crater was certainly formed relatively recently as the impact marks are still visible on the lunar surface. But in geological terms, recently means any time in the last 350 million years. While 18th June 1178 is certainly a date within the last 350 million years, it is odd that no other historical records anywhere have anything to say about it at all.

More recently, in 2001, a graduate student at the University of Arizona, called Paul Withers, did a bit more research. He calculated that a crater of that size would have been caused by an object that was somewhere between a half and two miles across. It would have thrown around ten million tons of debris into the Earth’s atmosphere. It would have caused a week long meteorite storm. There would have been maybe 50,000 meteorites an hour raining down all over the planet. Yet a search of historical records from Europe, the Middle East, China and Korea finds no mention of it.

It is much more likely that what the monks saw was an exploding meteorite, directly between them and the moon, hurtling straight towards them. Still pretty exciting, but with less catastrophic potential. Such an event would only be visible if you were in a very specific spot, or at least within a mile or so. This would explain why only five people saw it.

I love historical descriptions of events that are completely mystifying to us. They paint such a fascinating picture, yet explain nothing. I enjoy the gulfs of understanding between us and our predecessors as much as the similarities. If you’re in the mood for more unexplained phenomena from history, there are more here.

They Came From Space

11 30 meteorOn this day, in 1954, a meteorite fell near Sylacauga in Alabama. The largest piece of it which was recovered is known as the Hodges Fragment. It is called this because it hit a woman called Ann Hodges. Ann survived, and was able to walk away from the incident, though she was very badly bruised. The eight and a half pound rock had smashed through her roof, bounced off her large wooden radio and hit her in the side as she lay sleeping on her sofa. It’s a very rare thing for a person to be hit by a meteorite, It has been calculated that, in the US for example, a person will be hit by a meteorite once every 9,300 years. Oddly, her home was just over the road from the an establishment called the ‘Comet Drive-in Theater’.

Many people had observed the meteor in the sky. Over three states, they had heard explosions and seen its fiery trail. Some witnesses closer to the meteorite strike reported seeing a plane flying in the area, which was worrying. In 1954, people were pretty edgy about the Cold War and there was some concern that it might be something to do with the Russians. The meteorite was confiscated by the police and turned over to the United States Air Force for examination.

Once they had proved, beyond all doubt, that it was an extra-terrestrial object and not part of some terrible communist plot, the next problem was: who did the meteorite belong to? Hodges thought it was hers, as she was the person who had been hit by it. The owner of her rented house, Birdie Guy, thought as it had landed on her property, it should belong to her. There was a lot of legal wrangling and, eventually, Hodges paid Guy $500 for the rock. Both sides believed, falsely as it turned out, that there was a fortune to be made out of the meteorite. By the time they had finished deciding who it belonged to, everyone had forgotten about it.

The real winner in the Sylacauga meteorite incident was a local farmer called Julius McKinney, who was driving his mule cart when the animals ground to a halt and shied at something in the road. He got down to investigate, expecting to find a snake, but when he found a large black rock, he moved it to the verge and went on his way. When he heard about the Hodges meteorite, he went back, retrieved it and took it home and gave it to his children to play with. After a few days, he mentioned it to a friend who helped him find a buyer from the Smithsonian Institution in Washington DC. We don’t know how much he sold it for, but shortly afterwards he bought himself a house and a car.

11 30 ernst chladniToday is also the birthday of Ernst Chladni, who was born on this day in 1756. I mention him because he happens to be the first person to suggest the meteorites came from space. Before that, everyone thought they must come from volcanoes. Chladni worked mostly with sound experiments and also invented a couple of musical instruments called the euphon and the clavicylinder about which I have been able to find out disappointingly little.

Gift From Above

11 07 ensisheimOn this day in 1492, just before lunchtime, the people of the Alsation town of Ensisheim heard an enormous explosion, louder than anything they had ever heard. It was followed by a sound like thunder. According to some reports, it could be heard over ninety miles away. There was only one eyewitness who saw what actually happened. A young boy saw a burning, smoking object hurtle out of the sky and slam into a wheat field just outside the town.

He was able to lead the townspeople to a three foot deep hole in the ground. At the bottom was a large shiny black rock. It was a meteorite, though they didn’t know that. No one was quite sure what it meant or what to do about it. Eventually they decided to dig it out of the ground to have a proper look at it. It required quite a bit of effort. It was triangular in shape with three sharp corners and they guessed it weighed around 300 lbs. Then they used whatever tools they had handy to knock lumps off it to carry away as talismans. So someone had obviously decided that having a huge rock hurled at them from the heavens meant good luck.

When the town’s magistrate saw them, he made them stop and had the stone hauled into town and placed outside the door of the church, where it was very much admired. A few weeks later Holy Roman Emperor Maximilian happened by, on his way to fight the French. (If you read yesterday’s post, you might like to know that he was the father of Philip the Handsome.) He heard about the stone and ordered that it be sent to his castle. He puzzled over it for a few days and also decided that it was a good omen. He chipped off a couple more pieces, for himself and his friend Archduke Sigismund of Austria, and sent it back to the church. But he thought it would be best to fasten it with chains in the choir loft, because that would neutralise any malevolent forces it might carry.

Everyone was pretty excited about their sky rock. They wrote poems about it that were printed up and distributed far and wide. When Maximilian’s father died the following year, and he inherited the title of Archduke of Austria, everyone decided that the meteorite had predicted that too. Maximilian later tried to use the falling of the meteorite as proof that God wanted him to go on a crusade, but that didn’t really work out. He was pretty selective when it came to signs and portents though. In 1495 there was a considerable fall of meteorites near the town of Münckberge in Bavaria that were all said to be shaped like human heads wearing crowns, yet Maximilian chose to ignore them completely.

photo credit: Konrad Andrä, licenced to wikimedia commons
photo credit: Konrad Andrä, licensed under creative commons

People didn’t really know what meteorites were in the fifteenth century. They thought that the air could sometimes solidify and produce a huge rock. Or they thought the stones came from volcanoes somehow. It would be another 300 years before anybody suggested that they came from space. The Ensisheim meteor is the oldest documented meteorite in Europe that still survives. It’s not chained up in a choir loft any more though. You can see it in the town’s museum.