They were conducted by Joint Army/Navy Task Force One, headed by Vice Admiral William H. P. Blandy rather than by the Manhattan Project, which had developed nuclear weapons during World War II.

A fleet of 95 target ships was assembled in Bikini Lagoon and hit with two detonations of Fat Man plutonium implosion-type nuclear weapons of the kind dropped on Nagasaki in 1945, each with a yield of 23 kilotons of TNT (96 TJ).

"[1] The first proposal to test nuclear weapons against naval warships was made on August 16, 1945, by Lewis Strauss, future chairman of the Atomic Energy Commission.

This recommendation was accepted, and on January 11, 1946, President Harry S. Truman appointed Blandy as head of Army/Navy Joint Task Force One (JTF-1), which was created to conduct the tests.

When Blandy proposed an all-Navy board to evaluate the results, Senator McMahon complained to Truman that the Navy should not be "solely responsible for conducting operations which might well indeed determine its very existence.

[24] Timing was critical because Navy manpower required to move the ships was being released from active duty as part of the post-World War II demobilization, and civilian scientists knowledgeable about atomic weapons were leaving federal employment for college teaching positions.

[26] Of the possible places given serious consideration, including Ecuador's Galápagos Islands,[27] Bikini offered the most remote location with a large protected anchorage, suitable but not ideal weather,[28] and a small, easily moved population.

There was no signed agreement, but he reported by cable "their local chieftain, referred to as King Juda, arose and said that the natives of Bikini were very proud to be part of this wonderful undertaking.

[41] On July 26, 2016, the National Security Archive declassified and released the entire stock of footage shot by surveillance aircraft that flew over the nuclear test site just minutes after the bomb detonated.

This femme-fatale theme for nuclear weapons, combining seduction and destruction, is epitomized by the use in all languages, starting in 1946, of "bikini" as the name for a woman's two-piece bathing suit.

However, an investigation pointed to the conclusion that it had neither swum in the ocean nor escaped the blast; it had likely been safely aboard an observation vessel during the test, thus "absent without leave" from its post on Sakawa and showing up about the same time other surviving pigs were captured.

As with the two Los Alamos criticality accidents involving the earlier demon core, victims who were close enough to receive a lethal dose died, while those farther away recovered and survived.

Ten ships were sunk,[88] including the German heavy cruiser Prinz Eugen, which sank in December, five months after the test, because radioactivity prevented repairs to a leak in the hull.

Dentuda, with her crew safely away from their submarine, being submerged (thus avoiding the base surge) and outside the 1000-yard circle, escaped serious contamination and hull damage and was successfully decontaminated, repaired, and briefly returned to service.

[100] The underwater fireball took the form of a rapidly expanding hot gas bubble that pushed against the water, generating a supersonic hydraulic shock wave which crushed the hulls of nearby ships as it spread out.

[113] Twelve seconds after detonation, falling water from the column started to create a 900-foot (270 m) tall "base surge" resembling the mist at the bottom of a large waterfall.

[112] Tactical nuclear warfare advocates described the base surge as generation of very high sea states (GVHSS) disregarding radiation to emphasize the physical damage capable of disabling communication and radar equipment on warship superstructures.

Forensic examination of the wreck during multiple surveys since the test conclusively show that structural failure of hull plating along the starboard side allowed rapid flooding and capsized the ship.

[119] Blandy ordered tugs to tow the carrier to Enyu Island for beaching, but Saratoga and the surrounding water remained too radioactive for close approach until after she sank.

Unlike the Wilson cloud, a meteorological phenomenon in clean air, the base surge was a heavy fog bank of radioactive mist that rolled across all the target ships, coating their surfaces with fission products.

"[146] Warren had been chief of the medical section of the Manhattan Project[147] and was in charge of radiation safety at the Trinity test,[148] as well as of the on-ground inspections at Hiroshima and Nagasaki after the bombings.

[159] Captain L. H. Bibby, commanding officer of the apparently undamaged battleship New York, accused Warren's radsafe monitors of holding their Geiger counters too close to the deck.

After the August 10 decision to stop decontamination work at Bikini, the surviving target fleet was towed to Kwajalein Atoll where the live ammunition and fuel could be offloaded in uncontaminated water.

According to the official report, decontamination efforts "revealed conclusively that removal of radioactive contamination of the type encountered in the target vessels in test Baker cannot be accomplished successfully.

[173] In his preface, Bradley, a key member of the Radiological Safety Section at Bikini known as the "Geiger men", asserted that "the accounts of the actual explosions, however well intended, were liberally seasoned with fantasy and superstition, and the results of the tests have remained buried in the vaults of military security.

[176] Of the total mass of radioactive particles scattered by each explosion, 85% was unfissioned plutonium which produces alpha radiation not detected by film badges or Geiger counters.

[138] A summary of film badge readings (in roentgens) for July and August, when the largest number of personnel was involved, is listed below: Service members who participated in the cleanup of contaminated ships were exposed to unknown amounts of radiation.

[177] The 167 Bikini residents who were moved to the Rongerik Atoll prior to the Crossroads tests were unable to gather sufficient food or catch enough fish and shellfish to feed themselves in their new environment.

[33] After a successful trial in October 2010, the local government licensed a sole provider of dive expeditions on the nuclear ghost fleet at Bikini Atoll starting in 2011.

[185] Artist Bruce Conner made Crossroads, a 1976 video assembled from the official films, with an audio collage fashioned by Patrick Gleeson on a Moog synthesizer and a drone composition performed on an electric organ by Terry Riley.