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  • On these African plains some 60,000 years ago our ancestors began migrating north.

  • A trek that would ultimately give rise to modern day civilization. And it's nothing short of

  • a miracle that we've progressed as far as we have, especially in such a short amount

  • of time. It's really not that difficult to see why intelligent life may be extremely

  • sparse across the universe given how absurdly fortunate we've been. So many things could've

  • gone wrong along the way and so many times it almost did.

  • On the morning of the 12th of August, 1883, Mexican astronomer, José Bonilla, was observing

  • the Sun when numerous UFOs began to sweep across the solar disk. The objects were surrounded

  • by a coronal haze and left behind a trailing mist. The phenomenon continued for two consecutive

  • days and Bonilla counted 447 objects in total. As the event could not be explained the UFOs

  • were simply dismissed as birds, insects, or dust passing in front of the telescope.

  • But based upon Bonilla's description of the event coupled with an improved understanding of various

  • astronomical phenomena, an article published in 2011 hypothesized that the objects where

  • fragments of a comet nearly colliding with the Earth. The only bodies in the solar system

  • that leave trails and are surrounded by a bright haze are comets. And much like this

  • comet observed in 2006, we now know that fragmentation is a frequent occurrence. It is estimated

  • that the comet broke into more than 3,200 fragments ranging in size between 50-1000

  • meters in diameter and sailed past the earth at a distance of no more than a few thousand

  • kilometers. Had only one of these fragments struck the planet, it could have resulted

  • in millions of casualties. Had all or at least a significant portion of the fragments impacted

  • the Earth, we're looking at an extinction level event.

  • It's the middle of the Siberian taiga, around 7:00 AM, when a powerful explosion would lit

  • up the sky. An eyewitness 65 kilometers away from the blast accounts that:

  • "...the sky split in two and fire appeared high and wide over the forest. At that moment I became so

  • hot that I couldn't bear it, as if my shirt was on fire... I wanted to tear off my shirt

  • and throw it down but then the sky shut closed. A strong thump sounded and I was thrown a few meters."

  • Two decades later in 1927, the first expedition to the blast site would capture this footage.

  • Some 2000 km² of forest, some 80 million trees in total, had been completely

  • fattened by the event. The broad consensus is that an asteroid or comet, less than 200 meters wide,

  • exploded a few kilometers above ground and produced a fireball as demonstrated in this simulation.

  • Transposed over New York City its destructive power becomes a lot more apparent.

  • [Edward Lu] This one is a little bit harder to say. The one that..

  • Over Tunguska, the one that was slightly larger. Had that happened over a city.

  • Let's say New York City, we would have 7 million casualties.

  • At least, whatever the population of New York City is, they would be gone.

  • [Bill Nelson] Really?

  • While the two bombs dropped on Japan marked a dramatic end to the war, they also marked the beginning

  • of an entirely new kind of fear. A fear of annihilation by incompetence. Humans are fallible.

  • We make mistakes. And knowing this, coupled with the realization that one mistake could

  • result in apocalyptic levels of destruction, the likes of which had so far been reserved

  • by nature, this new kind of fear was undeniably justified.

  • In early October of 1960 a new early warning system on Greenland had just become operational.

  • In the event that the Soviet Union should launch an attack against the United States,

  • a level 5 warning would be sent to the command center located in Colorado. On October the 5th,

  • the number on the display suddenly changed from 0 to 1. Indicating that a low-risk unidentified

  • object had been detected. A bit strange but no immediate cause for alarm. But then the

  • number continued to climb until a level 5 warning was issued, meaning that long-range

  • missiles would strike the United States in less than 20 minutes. The alert quickly worked

  • its way up the chain of command and a slight panic ensued. But it was quickly eased by

  • the realization that Nikita Khrushchev, leader of the Soviet Union at the time, was currently

  • visiting the United States. Not exactly where you'd expect him to be in the event of a nuclear attack.

  • 20 minutes passed and the value of bottle caps remained the same. A subsequent

  • investigation revealed that the base on Greenland had mistaken the rising Moon for an incoming Soviet attack.

  • In the early morning of January the 24th, 1961, an American B-52 bomber carrying two

  • hydrogen bombs crashed into an empty field in the state of North Carolina. Officials

  • quickly issued a report stating that there was no cause for alarm and that there was

  • no danger of a nuclear explosion or radiation. However, declassified documents released in

  • 2013, reveal that one of the two bombs actually came extremely close to a full scale detonation.

  • Three out of four safety switches erroneously activated upon impact with the ground and

  • the slight separation of two wires was the only thing standing in the way of a nuclear

  • explosion. Had this 3.8 Mt bomb detonated, and had the wind condition been just right,

  • the radioactive fallout could've reached Washington, Philadelphia, and even New York.

  • In the early 1960s, tensions between the US and the Soviet Union is strained to the breaking

  • point and culminated in a situation known as the Cuban Missile Crisis. It is perhaps

  • the closest we've ever come to committing omnicide. The short version is that the US

  • installed nuclear missiles near the Soviet union, specifically in Turkey, so in response,

  • the Soviet Union installed nuclear missiles near the United States, specifically in Cuba.

  • The US would have none of that. "Hey, you can't do that! Only we are allowed to do that!"

  • said the United States. "I don't know what you're talking about?" the Soviet Union replied.

  • I'm paraphrasing of course as these where classified communications.

  • While the impasse in and of itself came extremely close to disaster,

  • one specific event stands out. After the US imposed a blockade to prevent the Soviet Union

  • from exporting even more missiles to Cuba, a Soviet submarine was detected near Cuban

  • shores. In an attempt to force the submarine to surface so that they could have a friendly

  • chat, multiple US naval destroyers dropped low intensity explosives to signal the submarine

  • to surface. However, the captain of the submarine misinterpreted this as an attack and ordered

  • his men to retaliate against one of the US destroyers by launching a nuclear-armed torpedo.

  • Fortunately, one of the two senior officers aboard disagreed with the captain's decision

  • and eventually managed to convince him that they should surface and await orders form

  • Moscow. And that's exactly what they did and thus the apocalypse had to reschedule.

  • On May the 23rd, 1967, all of the early warning systems across the United States ceased to function.

  • In fact, all manner of military communications and radar technology malfunction

  • simultaneously and it was interpreted as intentional jamming by the Soviets. Bomber planes immediately

  • scrambled and prepared to launch an attack. But as luck would have it just a few years prior, a branch of the US

  • military had begun observing solar activity and its effects on the Earth. And on this

  • day in 1967, the Sun had ejected a powerful solar storm that had stuck the planet and

  • knocked out military defenses and other equipment. Had a project for something as unrelated as

  • studying the Sun been delayed for just a few years, no one could've explained this nationwide

  • interference in time to prevent World War III.

  • In the mid 1980s squadrons of US aircrafts would often fly straight towards Soviet airspace,

  • thus triggering their early warning systems, only to turn around at the very last moment.

  • A form of psychological warfare that kept the Soviets on edge for an attack. In the

  • early hours of September the 26th, 1983, the command center just outside Moscow was awoken

  • by the sound of an alarm.

  • An intercontinental ballistic missile had just been launched by

  • the US and was now heading towards the Soviet Union. In the event of a nuclear attack by

  • the Americans it was standard procedure to launch an immediate counter-attack. It was

  • now up to the man in charge, Stanislav Petrov, to contact his superiors and to inform them

  • that a nuclear attack was imminent. A few minutes passed when four additional missiles

  • were detected. However, Petrov decided to go against his training and did nothing.

  • He reasoned that if the United States were to strike, the attack would likely involve hundreds

  • of missiles, not just a few. In other words, he suspected that this was a false-alarm.

  • But as he had no way of confirming his suspicions, he could only wait and hope for the best.

  • Fortunately, Petrov was correct in his assumption as evident by the fact that you are currently

  • breathing and a subsequent investigation revealed that sunlight, reflecting of off high altitude

  • clouds, was responsible for the anomaly.

  • On March the 31st, 1989, two American astronomers discovered that a week prior, on March the 22nd,

  • a 300 meters wide asteroid had come fairly close to the Earth. It had not come

  • close enough to pose any risk of impact and was even further away than the Moon but it's

  • still worth a mention as it passed through the exact position that the Earth had occupied

  • a mere six hours prior. Which is in and of itself extraordinarily close on the comic scale.

  • An impact with an asteroid of this size would obliterate almost everything within

  • a radius of 60-75 kilometers. Superimposed over Tokyo, one of the largest cities on Earth,

  • it looks like it would've been a rough day.

  • Some of you may remember that a few years ago there was a lot of eschatological prophecies

  • that the world would end in 2012. While the world is still spinning, as evident by the

  • rotation of this globe, we did narrowly escape a catastrophic event in July of 2012. On the

  • 23rd of July the Sun expelled something known as a coronal mass ejection or CME for short.

  • A CME is a release of large quantities of magnetized plasma and if it strikes the Earth

  • it can cause some serious damage to any and all electronic devices.

  • This was also one of the most powerful CMEs in recorded history.

  • And it blasted straight through the Earth's orbit.

  • Luckily for us, the Earth was on the other side when that eruption occurred but

  • due to the rotation of the Sun, had this eruption occurred just 9 days prior, we would've been

  • engulfed by that storm. If that had happened, and there's a 12% chance that it will happen in the

  • next 10 years, it could've taken us as much as a decade to fully recover. It's difficult

  • to overstate the ramifications of a CME on this scale. Worldwide power outages would

  • take weeks, months, or even years to resolve. Many satellites would have to be replaced.

  • Electronic equipment of all kinds would cease to function seemingly over night.

  • Medical, transportational, financial, military, national security, and other critical systems would

  • all be compromised or destroyed. Society would grind to a halt...

  • ...and be literally plunged into darkness for years to come.

  • Given how dependent we've become on electricity and various technologies

  • like the internet, it's difficult to image anything but global panic and chaos. It would

  • not have been the end of the world but it would no doubt have felt like it.

  • Declassified documents reveal that the US military has had over a thousand close calls

  • with nuclear weapons since the 1950s. Over a thousand times when cataclysmic devastation

  • was just narrowly avoided. And who knows how many near accidents the Russian military have

  • experienced or any of the other nuclear weapon states. Coupled with the destructive power

  • of natural events, it is truly a miracle that we've come as far as we have.

On these African plains some 60,000 years ago our ancestors began migrating north.

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アポカリプスでかすり傷 (Grazed by the Apocalypse)

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    shes96011 に公開 2021 年 01 月 14 日
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