The famous Doomsday Clock was set at three minutes until midnight, or theoretical doom.
The Doomsday Clock was invented in 1947 as a predictor of nuclear catastrophe.
These days, climate change is of an equal, if not greater, concern to the Bulletin's Science and Security Board in consultation with its Board of Sponsors, which includes 17 Nobel laureates.
The Doomsday Clock hasn't been this close to midnight since 1984 during the Cold War when communication between the U.S. and the Soviet Union had gone dark.
However, the closest the clock has ever been was in 1953 when the clock was moved to two minutes until midnight during testing of the first H bomb. The furthest it has ever been was in 1991, when the clock was at 17 minutes to midnight after the U.S. and Soviet Union agreed to reduce their nuclear arsenals.
“Today, unchecked climate change and a nuclear arms race resulting from modernization of huge arsenals pose extraordinary and undeniable threats to the continued existence of humanity,” Kennette Benedict, executive director of the Bulletin of the Atomic Scientists, said.
She added, "These failures of leadership endanger every person on Earth."
Sharon Squassoni, another board member and director of the Proliferation Prevention Program at the Center for Strategic and International Studies, said, "The risk from nuclear weapons is not that someone is going to press the button, but the existence of these weapons costs a lot of time, effort and money to keep them secure."
She added that nuclear disarmament efforts in most countries have "ground to a halt" and many nations are expanding, not scaling back, their nuclear capabilities.
Kennette Benedict had a little hope to offer at a news conference in Washington, D.C. after the Doomsday Clock was set.
She said, "We are not saying it is too late to take action but the window for action is closing rapidly."
She added, "We move the clock hand today to inspire action."
What do you think? Does the moving of the Doomsday Clock closer to catastrophe inspire you?