Misty Picture
Misty Picture was a test conducted on May 14 , 1987 by the United States Defense Nuclear Agency ( now part of the Defense Threat Reduction Agency ) involving the detonation of several thousand tons of conventional explosives to simulate the explosion of a small nuclear bomb . 
<triplet> Defense Nuclear Agency <subj> United States <obj> country <triplet> Defense Threat Reduction Agency <subj> United States <obj> country