Atomic scientists set their "Doomsday Clock" on Tuesday closer than ever to midnight, citing aggressive behavior by nuclear powers Russia, China and the United States, fraying nuclear arms control, co...

The Doomsday Clock is not a real clock, but a symbolic measure of how close humanity is to a global catastrophe.

The scientists cited risks of nuclear war, climate change, potential misuse of biotechnology and the increasing use of artificial intelligence without adequate controls as it made the annual announcem...