The "dry" two-stage device was known as "Morgenstern" and had a highly innovative secondary stage.
Post-shot analysis showed that the failure was caused by the premature heating of the secondary by the neutron flux of the primary.
The secondary consisted of a central sphere from which spikes were radiating, resembling a morning star / mace.
The spikes may have been[citation needed] an idea from physicist Edward Teller and colleagues to use implosive jets to compress the thermonuclear core.
It was more than two decades before weapons were designed that utilized a secondary concept similar to that first tested in the Koon shot.