They advance the time of the "apocalypse" 0:44
The Doomsday Clock, also known as the "Doomsday Clock," has been ticking for exactly 75 years.
But it is not just any watch.
Try to measure how close humanity is to destroying the world.
This Thursday, the clock was set at 100 seconds to midnight;
the same time since 2020.
The clock is not designed to categorically measure existential threats, but rather to spark conversations on difficult scientific topics like climate change, according to the Bulletin of Atomic Scientists, which created the clock in 1947.
"One hundred seconds to midnight reflects the Board's judgment that we are stuck in a dangerous time, one that brings neither stability nor security. Positive developments in 2021 have failed to offset negative long-term trends," said Sharon Squassoni, Co-Chair of the Bulletin's Science and Safety Council, which sets the time of the clock.
Squasson is also a Research Professor at the Institute for International Science and Technology Policy at The George Washington University.
The Doomsday Clock or Doomsday Clock stood at 100 seconds past midnight in 2022, the same time since 2020.
What is the Doomsday Clock?
The Bulletin of Atomic Scientists was a group of atomic scientists who worked on the Manhattan Project, the code name for the development of the atomic bomb during World War II.
Originally it was conceived to measure nuclear threats, but in 2007 the Bulletin made the decision to include climate change in its calculations.
Over the last three-quarters of a century, the time on the clock has changed, depending on how close scientists believe the human race is to total destruction.
Some years the weather changes, and others it doesn't.
The Doomsday Clock is set each year by experts from the Bulletin's Science and Safety Council in consultation with its Board of Sponsors, which includes 11 Nobel laureates.
Although the clock has been an effective wake-up call in reminding people of the cascading crises facing the planet, some have questioned the usefulness of the 75-year clock.
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Lawrence Krauss, a former member of the Bulletin's Board of Sponsors, said that while time has passed since the clock began ticking, it has been difficult to take its results seriously, as in recent decades it has come perilously close to the end of civilization.
As a theoretical physicist, Krauss has been concerned with how the clock is evaluated and determined today.
Every year, he said, when the clock creeps alarmingly close to midnight, scientists would have to measure how much available "space" is left before deciding how far the clock should move.
"Now the clock moves in seconds, before it was minutes," Krauss told CNN.
"It is clear that this is not a quantitative scientific assessment, but rather a qualitative one. What was always important is the movement of the watch, not its absolute value."
What happens if the clock strikes midnight?
The clock never struck midnight, and Rachel Bronson, president and CEO of the Bulletin, hopes it never does.
"When the clock strikes midnight, it means there has been some kind of nuclear exchange or catastrophic climate change that has wiped out humanity," he says.
"So we never want to get there and we won't know when we do."
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How accurate is the clock?
Clock time is not intended to measure threats, but rather to spark conversations and encourage public engagement on scientific issues such as climate change and nuclear disarmament.
If the watch is capable of doing that, then Bronson considers it a success.
When a new time is set on the clock, people listen, he said.
At the COP26 climate talks in Glasgow, UK Prime Minister Boris Johnson cited Doomsday Clock when discussing the climate crisis facing the world, Bronson noted.
Bronson said he hopes people will discuss whether they agree with his decision and have fruitful conversations about what the driving forces of change are.
COP26 concluded with a climate agreement.
In this he succeeded and in this the summit failed
It is still possible to turn back the clock with bold and concrete actions.
In fact, the hands have moved away before midnight, reaching 17 minutes before midnight in 1991, when the administration of President George HW Bush signed the Strategic Arms Reduction Treaty with the Soviet Union.
In 2016, the clock was three minutes before midnight as a result of the Iran nuclear deal and the Paris climate agreement.
What can an individual do to turn back the clock?
Don't underestimate the power of discussing these important issues with your colleagues, Bronson said.
"You may not feel it because you're not doing anything, but we know that public engagement moves (a) leader to do things," he said.
What can we do against climate change?
When it comes to climate change, look at your daily habits and see if there are small changes you can make in your life, like walking more often instead of driving and what you use to keep your house warm, Bronson explained.