Atomic shadows: The haunting imprints of Hiroshima and Nagasaki
When atomic bombs struck Hiroshima and Nagasaki in 1945, the intense light and heat from the explosions left only shadows of people on sidewalks, playgrounds, or stairs.
"Hibakusha" - this is the term used in Japan for those who survived the atomic bomb explosion. After their deaths, names are inscribed on memorials: there are 292,325 names in Hiroshima, and 165,409 in Nagasaki. The tragedy caught people in everyday situations at that time. A well-known example is the shadow of a person sitting on the steps at the Sumitomo Bank in Hiroshima. This fragment, known as the "Human Shadow of Death", is now displayed in the Hiroshima Peace Museum. It was acquired in 1971 due to the progressive fading of its outline.
How were "atomic shadows" created?
The scientific service Live Science details how "atomic shadows" were formed. Professor Michael Hartshorne, a retired radiology specialist from the University of New Mexico, whose research is cited by the website, explains the mechanism of their creation.
According to his explanation, after each bomb explosion, intense light and heat spread from the point of implosion, and people and objects in the path blocked what was behind them, leading to the "absorption" of light and energy. As a result of the bomb's detonation, the area around the figure remained exposed, becoming lighter.
The "atomic shadows" left behind helped preserve the original colours of the surface before the explosion. A nuclear fission reaction, which is the source of massive energy, occurs when a neutron strikes a heavy atomic nucleus, such as uranium-235 or plutonium-239 isotopes, causing the nucleus to split and triggering a chain reaction.
Atomic bombs were supposed to strike elsewhere
The American bomb "Little Boy" destroyed Hiroshima on 6 August 1945. Approximately 90,000 people died at that time. Meanwhile, Nagasaki was attacked three days later by the "Fat Man" bomb, which caused the deaths of 40,000 to 70,000 residents. The effects of this second explosion were likely mitigated by a hill surrounding one of the city's districts, which weakened the force of the shockwave.
Initially, the second attack was intended for Kokura, but poor weather conditions forced the pilots to change plans and select Nagasaki as an alternative target. This event inspired the Japanese phrase "Kokura's luck", signifying a narrow escape from danger. Kokura was also initially considered as the alternative target for the Hiroshima attack, should adverse weather conditions prevail.
