Amchitka - Milrow and Cannikin Tests

Milrow and Cannikin Tests

Though performed as part of the Nuclear Weapons Testing Program, " purpose of the Milrow test was to test an island, not a weapon." It was a "calibration shot", intended to produce data from which the impact of larger explosions could be predicted, and specifically, to determine whether the planned Cannikin detonation could be performed safely. Milrow was detonated on October 2, 1969, with an approximate yield of 1 to 1.2 megatons (4.2–5.0 PJ).

The shockwave reached the surface with an acceleration of over 35 g (340 m/s2), causing a dome of the Earth's surface, approximately 3 km (2 mi) in radius, to rise about 5 meters (16 ft). The blast "turned the surrounding sea to froth" and "forced geysers of mud and water from local streams and lakes 50 feet (15 m) into the air". A "surface collapse feature", also known as a subsidence crater, was formed by material collapsing into the cavity formed by the explosion.

Cannikin was intended to test the design of the Spartan anti-ballistic missile (ABM) interceptor – a high-yield warhead that "produced copious amounts of x-rays and minimized fission output and debris to prevent blackout of ABM radar systems." The test would "measure the yield of the device, measure the x-ray flux and spectrum, and assure deployment of a reliable design."