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Tick-tock: Everything you need to know about the Doomsday Clock


If you’ve never heard of the Doomsday Clock, everything is just fine. Go about your day and forget everything about whatever that was. However, if you have heard of it, you may -or may not- be interested in learning a little more. But if you want to carry on reading this there is a price to pay…

The good news is that the actual clock doesn’t exist, the bad news is that it’s a metaphor for how close we are to real-life, world-ending, Armageddon.

Invented in 1947, the clock is a grim side tranche of the Manhattan Project which, in essence, was the US-led body that oversaw the development and use of nuclear weapons. It was formed in 1942 and disbanded in 1946, almost a year to the day the Enola Gay dropped ‘Little Boy’ on Hiroshima, Japan at 8:15am on 6th August 1945.

A handful of the Project’s researchers were sufficiently alarmed by the sheer post-explosion carnage that they formed a group of international researchers called the Chicago Atomic Scientists. The premise was simple enough, collate as much information as possible to determine the likelihood of a nuclear event seeing off humankind, then publish an annual bulletin by using a metaphorical clock to display how close we are to midnight, i.e., the moment of hominid extinction.

So, in 1947, the Chicago Atomic Scientists' first-ever Bulletin of the Atomic Scientists was published. This contained the fruits of contemporary research on how much time humanity had left before all known life ended in a nuclear fireball. The answer was seven minutes to midnight.

Nuclear technology was still in its relative infancy in the 1940s. As a very rough guide, the nuclear event in Hiroshima killed 66,000 and a further 69,000 were wounded by a single 15-kiloton atomic bomb. Incidentally, the casualty figure is slightly less for Nagasaki, despite the bomb being 20 kilotons because the epicentre of the bomb was further away from a dense population. However, 39,000 still died and 29,000 were injured. Less we forget ‘injured’ doesn’t take into account the radiation poisoning that claimed lives in the years ahead.

But, these days, a standard nuclear device can yield anything from 500 kilotons to a megaton, that’s equivalent to one million tons of TNT. For more context, a 100-kiloton nuclear weapon, that’s ten-thousandths of a megaton bomb would lead to roughly 583,160 fatalities if dropped on New York City. And just to add a final twist to proceedings, according to the Stockholm International Peace Research Institute (SIPRI), the worldwide total inventory of nuclear weapons as of 2021 stood at 13,080, with more than 90% owned by either Russia or the United States.

Perhaps unsurprisingly, the time on the clock changes in line with the activity of the two main nuclear-warhead-rich countries as cited above. For example, in 1953, the clock reached two minutes to midnight when both counties began experimenting with thermonuclear weapons, aka Hydrogen or H-Bombs. These have the potential to be 1,000 times more powerful than the more conventional atomic bombs. But, in 1991, following the collapse of the Soviet Union, the clock went back to seventeen minutes to midnight, the furthest back in its history. This was, however, a short-lived respite.

In 2007, the Bulletin’s Science and Security Board - a collective of experts in science, technology and risk assessment, plus Nobel laureates, scholars and policy analysts - began to include more general risks to humanity outside of simple nuclear warfare, such as climate change, extreme weather events or ‘cyber-enabled disinformation’ that could lead to the ‘breakdown of global norms and institutions'. Other elements, breaches in biosecurity, Covid-19 for example, or the advancement of technologies that pose a risk to humanity are taken into consideration as well. And all the while there remains the ongoing nuclear threat, these days bolstered by non-NATO countries such as China, North Korea, Iran, Israel, Pakistan and India.

If this all sounds rather depressing, it’s because it is. In essence, since 1991’s seventeen minutes, time has been running out. By 2002 a full ten minutes had been wiped off the clock and in 2018 it was, once again, down to two minutes. In 2020, the minutes were gone and we were into seconds, 100 of them to be precise, but a further ten seconds have come off the Doomsday Clock since, and, as of 24th January 2023, we’re left with just a mere 90 seconds.

So, what does happen if the clock strikes midnight? The 1947 answer was easy, extinction via nuclear destruction. But now there are additional factors, with the most prominent being climate change, though determining that exact 'midnight' moment isn’t as simple as someone pressing the ‘do not press’ button.

There is one small, caveat, however. The Doomsday Clock wasn’t invented as a metaphorical countdown to our eradication but, as the Bulletins’ Scientists have always attested, as a means to spur humanity into doing something about the state of affairs that has put us in such a perilous position. Bulletin expert Prof. Robert Rosner calls the Doomsday Clock ‘the canary in the coal mine’, and while said canary is coughing up its toenails, it’s still not dead.

...As for the price to pay? Well, there are two. The first will be a few sleepless nights while you ruminate on the sheer horror of what happens if the clock strikes midnight. The other is quite simple...what can you do about it?