What Is the Doomsday Clock?
What is the Doomsday Clock? History, methodology, and what its seconds-to-midnight signal means for modern global risk debates.
Staff Reporting and Analysis. Produces source-backed reporting, explainers, and reference pages on nuclear risk, proliferation, and escalation dynamics.
Key Sources
Start with the strongest supporting documents and reporting behind this page.
Where This Matters Now
Recent articles where this concept is actively shaping the current crisis.
In Current Coverage
Is This Like the Cuban Missile Crisis? Comparing 1962 and 2026
A 1962 vs 2026 comparison of decision windows, nuclear proximity, escalation control, and why the Iran crisis is framed as a modern Cuban Missile moment.
2026-03-03
In Current Coverage
Able Archer 83: The 1983 Nuclear War Scare Explained
Able Archer 83 was a NATO drill in November 1983 that Moscow misread as a first strike, pushing Cold War tensions to their most dangerous point.
2026-03-03
In Current Coverage
Hiroshima and Nagasaki: What Happened When the Bombs Fell
On August 6 and 9, 1945, U.S. atomic bombs devastated Hiroshima and Nagasaki. Here is what happened, who died, and what radiation did after.
2026-03-03
Related Comparisons
Comparison pages that show how this concept plays out across rivalries, arsenals, and crisis analogies.
Related Concepts
Companion explainers that deepen the strategic logic around this topic.
Concept
What Is Mutually Assured Destruction (MAD)?
What is mutually assured destruction (MAD)? We explain the doctrine, Cold War logic, modern criticisms, and why MAD still shapes nuclear strategy.
2026-03-03
Concept
What Is Launch-on-Warning?
Launch-on-warning is a posture that allows missiles to launch before incoming warheads land. This explainer covers incentives, risks, and safeguards.
2026-03-04
Concept
What Is Second-Strike Capability?
Second-strike capability is the ability to absorb a first nuclear strike and still retaliate. This guide explains survivable forces and command resilience.
2026-03-04
What Is the Doomsday Clock?
The Doomsday Clock is a symbol that represents the likelihood of a human-made global catastrophe. Maintained by the Bulletin of the Atomic Scientists since 1947, the clock uses the imagery of midnight to convey how close humanity is to destroying itself.
A Brief History
The clock was created by scientists who had worked on the Manhattan Project. Originally focused solely on the threat of nuclear war, its scope has expanded over the decades to include climate change, disruptive technologies, and biosecurity threats.
Key Moments
- 1947: Clock created, set at 7 minutes to midnight
- 1953: Closest setting at the time — 2 minutes to midnight — after the US and Soviet Union test thermonuclear devices
- 1991: Furthest from midnight — 17 minutes — following the end of the Cold War
- 2023: Moved to 90 seconds to midnight, the closest ever at the time
- 2025: Moved to 89 seconds to midnight, a new record
How Is the Clock Set?
The clock is set annually by the Bulletin's Science and Security Board in consultation with its Board of Sponsors, which includes Nobel laureates. The board evaluates:
- Nuclear threats: Arsenal sizes, modernization programs, rhetoric, near-misses
- Climate change: Emissions trajectories, policy commitments, tipping points
- Disruptive technologies: AI, biotech, cyber weapons
- Biosecurity: Pandemic preparedness, gain-of-function research
What NukeClock Adds
NukeClock uses the official Doomsday Clock as its baseline. The NukeClock Live indicator is a separate, dynamic tool that adjusts more frequently based on current events. It is educational and meant to make nuclear risk more tangible — it is not an alternative to the official clock.