Scientists have been arguing about the health risks from radiation since the end of the 19th century, when radioactivity was ...

(It most likely obtained the blueprints for such a weapon from A.Q. Khan, the Pakistani nuclear scientist who sold the country designs for its nuclear centrifuges more than a quarter century ago.) ...

Intelligence indicates that Iran may be ready to transform its uranium stockpiles into a nuclear weapon within months, rather than the previously estimated year. Nonetheless, US officials ...