American experts from the Future of Life Institute simulated a nuclear conflict between Russia and the United States.
"We obviously don't know how many people will survive a nuclear war. But if it's even remotely as bad as this study predicts, it has no winners, merely losers," Time said.
Most of the US population will be killed immediately, whereas the ensuing nuclear winter will last for a decade.
If one side launches nuclear-capable missiles, the other side will retaliate in a maximum of ten minutes.
First nuclear explosions will burn all the electronics and power systems. The missiles will be launched targeting the locations of command and administrative posts and major cities.
A thermonuclear explosion in a populated area will lead to the emergence of a fireball with a temperature of the solar core and a radioactive mushroom cloud.
Everyone in the epicentre will be killed instantly, and those far away will be burned and blinded. The blast wave will demolish all buildings in its path, and the nuclear fire will finish the job scorching literally everything out.
An exchange of nuclear strikes will not be limited to explosions, electromagnetic impulses and radiation.
A nuclear winter will follow. Clouds of smoke will rise into the stratosphere and block sunshine. The earth will become very cold.
As a result, over five billion people, including from 60 to 99 percent of the population of the USA, Europe, Russia and China, will be killed in the chaos of nuclear Apocalypse.