The Doomsday Clock was manifested in 1947 by the Bulletin of the Atomic Scientists at the University of Chicago.  It is a symbolic clock that represents our proximity to global disaster posed by the threats of global nuclear war, biotechnology, and climate change.  Scientists move the minute hand closer and farther away from midnight sporadically when global events deem it necessary.

The initial setting of the Doomsday Clock was set at 11:53PM in 1947.  Just two years later it was moved to 3 minutes to midnight during the onset of the Cold War, when the Soviet Union began tests on the first atomic bomb.  The closet it ever inched towards midnight was in 1953, during the height of the Cold War, when it was brought to 2 minutes to midnight.  Since its inception that is the closest its been to midnight and 1991’s  11:43PM setting was the farthest from midnight it’s been.  That year saw the US and Soviet Union sign the Strategic Arms Reduction Treaty.

Since 2007 the clock remained at 5 minutes to midnight.  However, with the recent “worldwide cooperation to reduce nuclear arsenals and limit effect of climate change,” the clock has been set back one minute to 11:54PM in 2010, giving all of us reason for a sigh of relief.  The Bulletin of Atomic Sciences on the recent change:

It is 6 minutes to midnight. We are poised to bend the arc of history toward a world free of nuclear weapons. For the first time since atomic bombs were dropped in 1945, leaders of nuclear weapons states are cooperating to vastly reduce their arsenals and secure all nuclear bomb-making material. And for the first time ever, industrialized and developing countries alike are pledging to limit climate-changing gas emissions that could render our planet nearly uninhabitable. These unprecedented steps are signs of a growing political will to tackle the two gravest threats to civilization — the terror of nuclear weapons and runaway climate change.

[Via Gizmodo; Wiki]