Nuclear explosions can release high levels of radiation, an energy that removes electrons from atoms and can damage DNA.
In August 1945, the United States dropped two atomic bombs on the Japanese cities Hiroshima and Nagasaki, marking the first disastrous impact from nuclear energy.
In 1957, the United Nations created the International Atomic Energy Agency, an organization to promote peace and safety regulation standards with nuclear technologies.
The peace symbol was initially designed for the Direct Action Committee Against Nuclear War (DAC).
While areas around a nuclear explosion are immediately exposed, radiation can also remain in the atmosphere for decades, traveling great distances before it settles to the ground-level air or earth's surface.
In 1979, there was a nuclear power plant accident on Pennsylvania's Three Mile Island. The disaster exposed 2 million nearby residents to low-risk radiation (less than the strength of an x-ray).
It took 14 years and $975 million to clean up after Three Mile Island disaster.
The worst nuclear power plant accident in history occurred in the Ukraine in 1986. Explosions at the Chernobyl Power Plant killed 30 workers and caused the relocation of 300,000 residents.
The Chernobyl disaster released a hundred times more radiation than the atom bombs dropped on Nagasaki and Hiroshima in WWII.
The most powerful nuclear weapon ever detonated was Russia’s Tsar Bomba. It is also the single most physically powerful device ever created by man, the mushroom cloud was over 40 miles high and the base of the cloud was 25 miles wide.
Disposing of one's outer clothing can remove up to 90% of radioactive material after a nuclear disaster.
Japan has had three nuclear power plant accidents since 1999. The most recent accident in 2011 at the Fukushima Nuclear Power Plant occurred after a 9.0-magnitude earthquake and subsequent tsunami that damaged cooling systems. The government evacuated over 2,000 residents from a 20 kilometer radius surrounding the plant.
After Japan’s nuclear disaster in 2011, several countries have rethought the use of nuclear energy. Germany plans to close all of its reactors by 2022 and Italy and Switzerland have halted expanding their nuclear power.