The Doomsday Clock just moved half a minute closer to midnight. While that doesn’t necessarily mean that the world is about to come to a catastrophic end, it does raise questions about possible scenarios that we might soon face given this age of climate change, unprecedented technological innovation, and political tension. One doomsday scenario that keeps coming up during times of global instability is nuclear war.
Today, around 15,000 nuclear warheads are in existence, but only two have ever been used in warfare: the ones dropped over the Japanese cities of Hiroshima and Nagasaki over 70 years ago. Now, AsapSCIENCE has created a video that dissects the science behind nuclear bombs and illustrates the implications of an attack in case we need any reminder of exactly what one would entail.
Many factors affect a nuclear explosion, which means the impact of one will vary greatly depending on the weather, geographical layout of the target, weapon design, and point of detonation.
Because about one-third of the energy released by nuclear bombs is in the form of thermal radiation, which travels at the speed of light, a blast will be quickly followed by blinding light, causing flash blindness that can last for minutes. Assuming that the blast was caused by a 1 megaton bomb, which would be 80 times larger than the one that was dropped on Hiroshima, people within 21 km (13 miles) of the blast would experience temporary blindness from the flash on a clear day, as would those as far away as 85 km (52.8 miles) on a clear night.
Distance is crucial to your survival of a nuclear explosion as the blast will also release intense heat. Anyone within 11 km (6.8 miles) of the blast will likely suffer first degree thermal radiation burns. Any closer than that and you will suffer from second or third degree burns. The severity of tissue damage is not only dependent on your proximity to the center of the blast, but also such minor details as the color of your clothing — white may help reflect some of the energy of the blast, while darker clothes will absorb it.
Temperatures at the center of a blast have been estimated to reach 300,000 degrees Celsius (540,000 degrees Fahrenheit), which means if you’re right in the middle of it, you’ll be turned to ash almost instantly. If you’re farther away, the massive force and sudden changes in air pressure, which are strong enough to knock buildings down, put you at serious risk of being killed by debris.
Should you survive all that, you still have to deal with the effects of radiation and the nuclear fallout. Studies of the survivors of the bombings that occurred during WWII reveal an increase of about 10 to 44 percent in their chances of developing cancer, and that bomb was far less powerful than the ones available today. However, with international treaties now in place to prevent any future use of nuclear weapons (and, hopefully, now that we’ve seen first-hand the true repercussions of a nuclear attack), history will not ever repeat itself.