03-06-2025
Demon Core: World War II-Era Nuclear Mass, Manhattan Project Relic That Killed Two Scientists
Created for a third atomic bomb, the Demon Core never left the lab but still killed two scientists in chilling, real-life radiation accidents.
In the final days of World War II, a small, unassuming sphere of plutonium earned a deadly nickname and came to be known as the Demon Core.
Crafted as a key component of the atomic bomb, this metal ball of destruction never saw battle but claimed the lives of two brilliant scientists in fatal accidents.
It was the third atom bomb that was designed but it was never used or detonated.
The Demon Core came into public attention after Dr Ben Miles shared a reel on Instagram explaining how after being left behind the Demon Core became an object of 'deadly scientific curiosity". The reel was shared as a part of his series 'Scientifically Interesting Ways To Die".
A Deadly Remnant of the Atomic Age
The 'Demon Core" was a 6.2-kilogram sub-critical mass of plutonium designed as the core of a third atomic bomb during World War II. Created under the US Manhattan Project, it was intended for use against Japan after Hiroshima and Nagasaki—but Japan's surrender halted the plan.
Harry Daghlian: First Victim of the Demon Core
Harry Daghlian was a 24-year-old physicist working at Los Alamos in 1945. A rising talent, he had joined the Manhattan Project to study neutron behavior in fissile materials. On August 21, 1945, while performing a criticality experiment alone, Daghlian accidentally dropped a tungsten brick onto the plutonium core, initiating a burst of radiation.
Though he quickly removed it, he had already received a fatal dose. Daghlian died 25 days later from acute radiation poisoning, becoming the core's first victim.
Louis Slotin Tried To Pry It Open With A Screwdriver
Louis Slotin, a Canadian physicist and bomb assembly expert, took over similar experiments with the core. Known for his hands-on approach and disregard for safety protocols, Slotin became one of the few people who could assemble a bomb core manually. On May 21, 1946, Slotin was demonstrating a criticality test to colleagues. Using a screwdriver to separate two beryllium hemispheres around the core, the tool slipped and ended up triggering a burst of blue light and radiation. Slotin quickly disassembled the sphere, saving others in the room. He died nine days later from massive radiation exposure.
How Demon Core Killed
Both deaths were caused by sudden criticality. Criticality is an uncontrolled nuclear reaction that released lethal doses of neutron and gamma radiation in microseconds. This exposure destroyed bone marrow, burned internal organs and triggered systemic failure. Acute radiation poisoning, depending on dosage, leads to nausea, burns, cell death, and in high doses, certain death.
Radiation at high doses damages DNA, disrupts cellular replication, and breaks down the body's ability to heal. Victims of criticality accidents often die from infections, organ failure, or internal bleeding triggered by cell destruction.
Where Is It Now
Following Slotin's death, scientists halted all hands-on criticality tests. The Demon Core was later melted down and reused in other nuclear experiments. Today, it no longer exists as a single object.
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tags :
atom bomb hiroshima manhattan project Nagasaki
Location :
New Delhi, India, India
First Published:
June 03, 2025, 20:47 IST
News viral Demon Core: World War II-Era Nuclear Mass, Manhattan Project Relic That Killed Two Scientists
