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Clock of catastrophe -

The Doomsday Clock is a symbol that represents the likelihood of a man-made global catastrophe.

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Bulletin of the Atomic Scientists -

It's been maintained since 1947 by the members of the Bulletin of the Atomic Scientists, itself founded in 1945 by Albert Einstein and University of Chicago scientists who helped develop the first atomic weapons in the Manhattan Project.

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A metaphor for threats -

The clock serves as a metaphor for hazards to our world from unchecked scientific and technical advances using the imagery of apocalypse (midnight) and the contemporary idiom of nuclear explosion (countdown to zero) to convey threats to humanity and the planet.

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Who sets the Doomsday Clock? -

The clock is set every year by the Bulletin's Science and Security Board. It's original setting in 1947 was seven minutes to midnight. Since then its timeline has been adjusted to reflect the perceived threat from nuclear weapons, climate change, and disruptive technologies in other domains. To turn the clock back is to revisit some of the most frightening and potentially catastrophic episodes in the history of humanity.

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1949: 3 minutes to midnight (23h57) -

On August 29, 1949, the Soviet Union carried out its first nuclear test, detonating an atomic bomb, the RDS-1, thus officially starting the nuclear arms race.

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1953: 2 minutes to midnight (23h58) -

The United States tests its first thermonuclear device, in November 1952 at Eniwetok Atoll in the Pacific Proving Ground in the Marshall Islands, as part of Operation Ivy. The USSR responds with a similar test in August 1953. This remained the clock's closest approach to midnight (tied in 2018) until 2020.

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1960: 7 minutes to midnight (23h53) -

Despite a series of regional conflicts including the Suez Crisis of 1956 (pictured), the 1958 Second Taiwan Strait Crisis, and the 1958 Lebanon crisis, the clock is put back five minutes in 1960 due in part to increased scientific cooperation and public understanding of the dangers of nuclear weapons.

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1963: 12 minutes to midnight (23h48) -

The Partial Test Ban Treaty signed by the governments of the Soviet Union, the United Kingdom, and the United States in Moscow on August 5, 1963 set the clock back to 23h48.

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1968: 7 minutes to midnight (23h53) -

The clock edges towards midnight again as involvement of the United States in the Vietnam War intensifies. The Indo-Pakistani War of 1965 and the Six-Day War in 1967 are also determining factors. Meanwhile, France and China join the nuclear arms race.

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1969: 10 minutes to midnight (23h50) -

Every nation in the world, with the notable exceptions of India, Israel, and Pakistan, signs the Nuclear Non-Proliferation Treaty. The treaty was negotiated by the Eighteen Nation Committee on Disarmament, a United Nations-sponsored organization based in Geneva, Switzerland. It was signed on July 1, 1968 and became effective on March 5, 1970.

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1972: 12 minutes to midnight (23h48) -

A wave of renewed optimism sweeps the world as the United States and the Soviet Union sign the first Strategic Arms Limitation Treaty (SALT I) and the Anti-Ballistic Missile (ABM) Treaty. The clock drops back 120 seconds to 12 minutes before midnight as Richard Nixon and Leonid Brezhnev close the deal in Moscow.

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1974: 9 minutes to midnight (23h51) -

India's testing of a nuclear device and the stalling of the vital SALT II talks edges the clock forward. Pictured: a crater marks the site of the first Indian underground nuclear test conducted on May 18, 1974 at Pokhran in the desert state of Rajasthan.

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1980: 7 minutes to midnight (23h53) -

The Soviet Union's invasion of Afghanistan in December 1979 sees the US Senate refuse to ratify the SALT II agreement.

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1981: 4 minutes to midnight (23h56) -

The world is in turmoil: rising tensions between the United States and the Soviet Union contribute to the danger of nuclear annihilation; the US pulls out of the 1980 Olympic Summer Games; the Iran hostage crisis (pictured) makes world headlines; the Iran-Iraq conflict continues; martial law is declared in Poland; apartheid in South Africa achieves new levels of brutality; and widespread human rights violations are witnessed around the globe.

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1984: 3 minutes to midnight (23h57) -

Further escalation of the tensions between the United States and the Soviet Union are exemplified with the deployment in Western Europe of Pershing II medium-range ballistic missile and cruise missiles. Meanwhile, the ongoing Soviet–Afghan War only serves to intensify the Cold War. And the Soviet Union announce a boycott of the 1984 Summer Olympic Games in Los Angeles. Pictured is a banner that reads "Refuse Cruise" seen at a demonstration by the Campaign for Nuclear Disarmament (CND) against the hosting by the UK of US nuclear cruise missiles on British soil.

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1988: 6 minutes to midnight (23h54) -

A thaw in the Cold War sees the clock gain three minutes as Ronald Reagan and Mikhail Gorbachev sign the Intermediate-Range Nuclear Forces Treaty in Washington, D.C. on December 8, 1987, effective June 1, 1988.

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1990: 10 minutes to midnight (23h50) -

The fall of the Berlin Wall on November 1990 and the Iron Curtain, along with the reunification of Germany, sees the beginning of the end of the Cold War.

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1991: 17 minutes from midnight (23h43) -

The dissolution of the Soviet Union on December 26, 1991 sees the hands of the Doomsday Clock set back 420 seconds to 17 minutes—to date the farthest from midnight the Doomsday Clock has been since its inception.  

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1995: 14 minutes to midnight (23h46) -

Concerns mount over post-Soviet Union nuclear proliferation of weapons and brainpower. At the same time, and despite the signing of various treaties, global military spending continues at Cold War levels.

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1998: 9 minutes from midnight (23h51) -

Both India and Pakistan detonate nuclear weapons in underground tests: Pakistan's Chagai-I project takes place at Ras Koh Hills, while the remote Thar Desert region (pictured) serves as the location for India's Pokhran-II series of detonations.

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2002: 7 minutes from midnight (23h53) -

The global nuclear disarmament initiative loses momentum and the United States, concerned about the possibility of a nuclear terrorist attack due to the amount of weapon-grade nuclear materials that are unsecured and unaccounted for worldwide, rejects a series of rams controls and treaties.

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2007: 5 minutes to midnight (23h55) -

The clock edges forward after North Korea tests a nuclear weapon in 2006. At the same time, Iran's nuclear ambitions become cause for concern. And in a sign of the times, after assessing the dangers posed to civilization, climate change is added to the prospect of nuclear annihilation as the greatest threats to humanity.

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2010: 6 minutes to midnight (23h54) -

The Clock edges back 60 seconds after the 2009 United Nations Climate Change Conference in Copenhagen results in the developing and industrialized countries agreeing to take responsibility for carbon emissions and to limit global temperature rise to 2°C (35.6°F).

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2012: 5 minutes to midnight (23h55) -

The lack of global political will to address urgent global climate change issues nudges the clock another minute towards midnight. Of equal concern are nuclear weapons stockpiles, the potential for regional nuclear conflict, and nuclear power safety.

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2015: 3 minutes to midnight (23h57) -

The apparent inability of governments around the world to tackle global climate change, plus the modernization of nuclear weapons in the United States and Russia, and the problem of nuclear waste, takes another 120 seconds off the clock.

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2017: 2.5 minutes to midnight (23h57.30) -

US President Donald Trump's alarmist rhetoric over nuclear weapons, the threat of a renewed arms race between the US and Russia, and his administration's refusal to accept scientific consensus over climate change, is enough to shave off another 90 seconds.

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2018: 2 minutes to midnight (23h58) -

The clock matches its 1958 2-minute warning after the US withdraws from the 2015 Paris Agreement.

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2019: 2 minutes to midnight (23h58) -

In 2019, the Doomsday Clock remained at 2 minutes to midnight due to unresolved issues involving climate change and because of the threat posed by information warfare such as misuse of AI and synthetic biology, and cyberwarfare.

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2020: 100 seconds to midnight (23h58.2) -

In 2020, the unit of time was announced in seconds (100) to emphasize "the most dangerous situation that humanity has ever faced," according to the Bulletin of the Atomic Scientists.

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2021/2022: 100 seconds to midnight -

In 2021 and 2022, the Bulletin reaffirmed the "100 seconds to midnight" time setting, reiterating the failure of world leaders to deal with the increased threats of nuclear war along with the continued neglect of climate change.

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2023: 90 seconds to midnight (23h58.5) -

In 2023, the clock was moved 10 seconds closer to midnight, leaving us just 90 seconds away from doomsday. This was in response to Russia's attack on Ukraine and the imminent threat of nuclear war. “We are sending a message that the situation is becoming more urgent,” said Rachel Bronson, President of the Bulletin of Atomic Scientists. "Crises are more likely to happen and have broader consequences and longer standing effects.” Other threats to humanity mentioned included "nuclear weapon proliferation in China, Iran increasing its uranium enrichment, missile tests in North Korea, future pandemics from animal diseases, pathogens from lab mistakes, “disruptive technologies,” and worsening climate change."

Sources: (BBC) (Bulletin of the Atomic Scientists) (CTBTO)

See also: After Chernobyl: meet the Ukrainian ghost city

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