In the history of mankind, inhabited cities were only once exposed to the atomic bombing. This happened in August 1945, when the 33rd US President Harry Truman ordered to drop two atomic bombs on the cities of Hiroshima and Nagasaki. In April 1986, an accident at the fourth nuclear reactor occurred at the Chernobyl nuclear power plant in the USSR in the territory of today’s Ukraine. The consequences of both events were terrible.
As a result of the accident at the power plant, almost all of Europe suffered from radiation. Some localities close to the nuclear power plant had to be evacuated. And in a radius of about 30 kilometers around, an exclusion zone was created, in which it was forbidden to be.
In both cases, the cause of the tragedy was a nuclear disaster, but the magnitude of the consequences is different. Thus, approximately 1.6 million people currently live and work in Hiroshima and Nagasaki, while in the Chernobyl exclusion zone there are still almost no people.
As you know, it is impossible to live in the territory where a nuclear explosion occurred. So what is the difference between the two cases? And why did people return to Nagasaki and Hiroshima, but not to Chernobyl?
At first glance, the cause of both tragedies is the same – a nuclear cataclysm. But the strength and nature of these events differ dramatically.
So, the amount of uranium in bombs dropped on Japanese cities was much less than in nuclear fuel at the Chernobyl nuclear power plant. For example, the Kid’s bomb dropped on Hiroshima contained 64 kilograms of uranium. And only 700 grams of them were involved in the reaction. And in one rector at the nuclear station was 180 tons of uranium.
Also, the residual radiation after the bombing in Japanese cities was not able to stay in the atmosphere for a long time. Because, firstly, the explosion of both bombs occurred in the air, about 500 meters from the surface of the earth.
If a nuclear explosion occurs in mid-air, the blast wave travels upward. As a result of this, most of the harmful emissions do not fall into the ground, it is carried away by air masses.
Secondly, most of the radionuclides disintegrate within 2-3 minutes. Of course, in the epicenters of the explosions, radiation was very high in the first few hours after the disaster. However, it quickly came to naught.
A month after the explosion, American researchers took measurements of the level of radiation in the Hiroshima area and came to the conclusion that the city poses no danger to the military. It was noticed that the plants affected after the explosion started again to shoot and bloom. It also speaks in favor of the fact that radiation is scattered.
And although at that time the level of radiation in cities was even higher than the norm, gradually people began to return to them. Then, few people knew about radiation sickness, and only years later, doctors will notice that there are much more patients with oncology in these areas.
However, every year the situation became better and better and the land safer. And now in Hiroshima and Nagasaki you can live and not be afraid for your health.
In Chernobyl, everything developed according to a different scenario. As mentioned earlier, in the exploded reactor there were about 180 tons of radioactive fuel, 3600 kilograms of uranium. And during the explosion, about 500 times more harmful substances were released into the atmosphere than during the explosions in Japan.
An explosion at a nuclear power plant occurred on the ground, which accelerated the spread of radioactive substances, affecting a large area. For comparison, in an explosion in the air, one wave is obtained that spreads harmful elements, and the spread itself has a one-time character. In the case of an explosion at a nuclear power plant, there were much more emissions, and they continued for a month.
In addition, radioactive fuel from the Chernobyl nuclear power plant contained a large number of such harmful elements as iodine-13 and americium-241, cesium-137, plutonium-239 and strontium-90. In Japanese cities, these substances were not found.
In Chernobyl, a decrease in the background radiation is currently observed. Some harmful elements have disappeared. However, many will remain in the ground for thousands of years. And that means that the day when it will be possible to populate Chernobyl will come soon.