Radiation that has lengthy effect.

How Nuclear Radiation Works

Nuclear Explosion

You've probably heard people talk about radiation both in fiction and in real life. For example, when the

Enterprise approaches a star on "Star Trek," a member of the crew might warn about an increase in 

radiation levels. In Tom Clancy's book "The Hunt for Red October," a Russian submarine has a nuclear

reactor accident with radiation leakage that forces the crew to abandon ship. At Three Mile Island and Chernobyl, nuclear power plants released radioactive substances into the atmosphere during nuclear accidents. And in the aftermath of the March 2011 earthquake and tsunami that struck Japan, a nuclear crisis raised fears about radiation and questions about the safety of nuclear power.
Nuclear radiation can be both extremely beneficial and
extremely dangerous. It just depends on how you use it.

Little boy (worst example)

 X-ray machines, some types of sterilization equipment and nuclear power plants all use nuclear radiation -- but so do nuclear weapons. Nuclear materials (that is, substances that emit nuclear radiation) are fairly common and have found their
 way into our normal vocabularies in many different ways.


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