The Doomsday Clock is a theoretical clock designed to show how close we are to destroying our own world. The clock was conceived in 1947 by the Bulletin of Atomic Scientists when the Soviet Union and the US were possibly entering into a nuclear arms race. The minute hand has been moved 23 times since then. Sometimes further from midnight; sometimes closer to midnight.
The Science and Security Board takes into consideration several things that might bring us closer to doomsday. This includes risks such as nuclear weapons and climate change, and whether countries are taking steps to address the risks or have taken actions that increase the risks.
On January 25th, 2018, the Science and Security Board at the Bulletin of Atomic Scientists set the time to two minutes to midnight. This is 30 seconds closer than in 2017 and it is only the second time ever that the minute hand has been set so close to midnight.
You can learn more information by visiting https://thebulletin.org/
The minute hand of the Doomsday Clock is currently set to two minutes before midnight.