Nuclear Fallout
<p><b >Fallout</b> is the residual radioactive material propelled into the upper atmosphere following a <a href="http://en.wikipedia.org/wiki/Nuclear_explosion" title="Nuclear explosion" >nuclear blast</a> or a <a href="http://en.wikipedia.org/wiki/Nuclear_reaction" title="Nuclear reaction" >nuclear reaction</a> conducted in an unshielded facility, so called because it "falls out" of the sky after the explosion and <a href="http://en.wikipedia.org/wiki/Shock_wave" title="Shock wave" >shock wave</a> have passed. It commonly refers to the<a href="http://en.wikipedia.org/wiki/Radioactive" title="Radioactive" class="mw-redirect" >radioactive</a> dust and ash created when a <a href="http://en.wikipedia.org/wiki/Nuclear_weapon" title="Nuclear weapon" >nuclear weapon</a> explodes, but this dust can also be originated in a damaged nuclear plant. This radioactive dust, consisting of material either directly vaporized by a nuclear blast or charged by exposure, is a highly dangerous kind of <a href="http://en.wikipedia.org/wiki/Radioactive_contamination" title="Radioactive contamination" >radioactive contamination</a>. It can lead to the contamination of <a href="http://en.wikipedia.org/wiki/Aquifers" title="Aquifers" class="mw-redirect" >aquifers</a> or <a href="http://en.wikipedia.org/wiki/Soil" title="Soil" >soil</a> and devastate the affected ecosystems years after the initial exposure.</p>