Nuclear weapon test Union (yield 6.9 Mt) on <a href="https://en.wikipedia.org/wiki/Bikini_Atoll" class="extiw" title="en:Bikini Atoll">Bikini Atoll</a>. The test was part of the <a href="https://en.wikipedia.org/wiki/Operation_Castle" class="extiw" title="en:Operation Castle">Operation Castle</a>.
<a href="https://en.wikipedia.org/wiki/United_States_Department_of_Energy" class="extiw" title="en:United States Department of Energy">United States Department of Energy</a>
1954-04-26
<a rel="nofollow" class="external text" href="http://www.cddc.vt.edu/host/atomic/testpix/">www.cddc.vt.edu</a>