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Culture, history and society

Culture, history and society

A brief history of the Doomsday Clock: from nuclear risk to pandemics and climate change

03 Sep 2020 James Dacey

Video transcript

We’re just 100 seconds from midnight on the Doomsday Clock – a metaphor created by the Bulletin of the Atomic Scientists in 1947.

The clock indicates how near we are to a humanity-ending catastrophe. We’ve never been this close to midnight before.

And what’s more, the last time the clock was set on 23rd January 2020, before the COVID-19 outbreak became a global pandemic. With the year we’ve had so far, who would bet against the clock ticking even closer to midnight in 2021?

But what is the Doomsday Clock and how is its time determined?

The clock emerged from the concerns of the physics community immediately after the Second World War.

Many scientists and engineers had taken part in the Manhattan Project, which developed the atomic bombs that the United States dropped on Hiroshima and Nagasaki in August 1945.

Just a few months after the war finished, two University of Chicago physicists – Eugene Rabinowitch and Hyman Goldsmith – launched the Bulletin of the Atomic Scientists.

This journal aimed to encourage scientists to engage in political issues. The war had made it painfully clear that even theoretical physics is no longer an abstract intellectual exercise, somehow divorced from the real-world.

Part of the journal’s remit was to consider future dangers. Or as Rabinowitch poetically put it: “to manage the dangerous presents of Pandora’s box of modern science”.

It was a desire to communicate these risks to the public that led to the Doomsday Clock being set up in 1947.

The idea emerged from the cover of the June edition that year, an artwork created by Martyl Langsdorf. Langsdorf placed the first clock at seven minutes to midnight for purely aesthetic reasons, but its subsequent positions were set by Rabinowitch.

When he died in 1973, a science and security board took over that responsibility, in consultation with the journal’s board of sponsors.

Over the years, the clock hands ticked further or closer to midnight depending on prevailing nuclear concerns.

Prior to this year, the closest the Doomsday Clock had been to midnight was in 1953. Then, it was set to 11:58 after both the US and the Soviet Union carried out hydrogen-bomb tests the previous year.

Its furthest distance from midnight came in 1991 when the clock was moved back to 11:43. That optimism followed the end of the Cold War and the signing of the Strategic Arms Reduction Treaty, which led to deep cuts in US and Soviet nuclear-weapon arsenals.

Another key change occurred in 2007 when the Doomsday Clock started factoring in the risk of climate change. Since then it has also started considering new disruptive technologies, including artificial intelligence and gene editing.

Each year, the Bulletin’s panel of experts meet in Chicago in November to vigorously debate whether the time should be reset – with the decision confirmed and announced in January.

The decision to set the 2020 clock so close to midnight was based on a combination of factors.
They included the continuing existence of nuclear arsenals coupled with the lapse of several major arms-control treaties, and America’s decision to quit the Iran nuclear deal.

Given the clock’s gloomy connotations, it’s not surprising that it has attracted some criticism over the years.

Commentators have accused the Bulletin of everything from inconsistency, historical pessimism, lack of clarity around its methodology, and political bias. Though it should be noted that the clock has moved forward and back during both Democratic and Republican administrations in the US.

Whatever people think of the clock, it has consistently met its goal of triggering public debate about the role of science in society.

There’s no doubt the COVID-19 pandemic will play into 2021 decision. Progress towards vaccines will surely be crucial, as might the tensions surrounding the US presidential elections in November.

Find out more about the Doomsday clock in the September 2020 issue of Physics World.

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