1. Fallout can stay in the atmosphere for years
Explosion of the “Seminole” nuclear device at Enewetak Atoll in the Pacific Ocean on June 6, 1956. CORBIS/Corbis
Nuclear explosions create dangerous fallout – residual radioactive material that travels high in the air, cools to dust, and eventually settles to the ground, poisoning it in the process.
Most fallout from a nuclear explosion takes between a day and a week to return to the ground, said Zaijing Sun, a nuclear physicist at the University of Nevada in Las Vegas.
But some fallout is thrown so high into the atmosphere, up to 50 miles high, that it can linger for months or even years before falling back to the surface, Sun added.
Sun works in the Health, Environment and Radiation Detection Research Group at UNLV which studies radioactive waste management, as well as the applications of radiology and nuclear physics for medical purposes.