I knew that the famous two-piece bathing suit got its name from the Bikini Atoll weapon tests, but I didn’t realize just how early those tests were — July 1946:
The two-piece swimsuit was introduced within days of the first nuclear test on the atoll, when the name of the island was in the news. Introduced just weeks after the one-piece “Atome” was widely advertised as the “smallest bathing suit in the world”, it was said that the bikini “split the atom”.
As Todd mentioned, there’s something fascinating about an atomic cannon, like the one demonstrated in the Upshot-Knothole Grable test:
Grable was the second of only two gun-type warheads ever detonated (the first was Little Boy, the weapon used against Hiroshima; all other atomic weapons were implosion-type weapons).
The shell, designated a Mark 9 nuclear weapon, had a diameter of 280 mm (11.02 in), was 138 cm (54.4 in) long and weighed 364 kg (803 lb). The M65 Atomic Cannon from which it was fired had a muzzle velocity of 625 m/s (2,060 ft/s), for a nominal range of 32 km (20 mi), and weighed 77 metric tons (85 t).
The detonation of Grable occurred 19 seconds after its firing. It detonated over 11,000 yards (over 10 km, 6.25 mi) away from the gun it was fired from, over a part of the Nevada Test Site known as Frenchman Flat. The explosion was an air burst of 160 m (524 ft) above the ground (7 m (24 ft) above its designated burst altitude), 26 m (87 ft) west and 41 m (136 ft) south of its target (slightly uprange). Its yield was estimated at 15 kilotons, around the same level as Little Boy.
An anomalous feature of the blast was the formation of a precursor, a second shock front ahead of the incident wave. This precursor was formed when the shock wave reflected off the ground and surpassed the incident wave and Mach stem due to a heated ground air layer and the low burst height. It resulted in a lower overpressure, but higher overall dynamic pressure, which inflicted much more damage on drag sensitive targets such as jeeps and personnel carriers. This led strategists to rethink the importance of low air bursts in tactical nuclear warfare.
I’m sure an atomic cannon sounds preposterous now, like a nuclear hand grenade, but I suspect the real problem with the cannon’s limited range was that it limited the threat to a very narrow portion of the battlefront, when the same atomic weapon could instead be dropped just about anywhere via bomber.
I was surprised by the brevity of the discussion of the Hardtack Teak test, which launched a 3.8-Megaton warhead into the upper atmosphere by way of glorified V-2 rocket — in 1958, one year after Sputnik. This is the test that brought EMP to our attention:
The Apia Observatory in Western Samoa approximately 2,000 miles to the south described the “. . . violent magnetic disturbance,” which heralded “. . . the most brilliant manifestation of the Aurora Australis [Southern Lights] ever seen in Samoa.” The resulting persistent ionization of the low-density atmosphere cut high frequency radio communications with New Zealand for six hours.
In Hawaii, where there had been no announcement of the test, the TEAK fireball turned from light yellow to dark yellow to orange to red. “The red spread in a semi-circular manner until it seemed to engulf a large part of the horizon,” one resident told the Honolulu Star-Bulletin. The red glow remained clearly visible in the southwestern sky for half an hour. In Honolulu, military and civilian air traffic communications were interrupted for several hours. At the AFSWP’s Armed Forces Special Weapons Project offices in the Pentagon, Admiral Parker grew concerned for the personnel on Johnston Island as hour after hour passed with no word regarding the test. Finally, some eight hours after TEAK had occurred, the word that all was well came from Luedecke, the commander of Joint Task Force 7 and soon to be General Manager of the AEC. The communications blackout worried others as well. Later AFSWP learned that one of the first radio messages received at Johnston Island once communications was restored was: “Are you still there?”
It’s the footage of the multi-Megaton hydrogen bombs, by the way, that’s truly terrifying. The multi-kiloton atomic bomb blasts seem “reasonable” by comparison.
Anyway, the movie ends with a rather disturbing Chinese propaganda piece you simply must see for yourself, complete with saber-swinging cavalry and hip-shooting infantry charging into the breech made by an atom bomb.
Western analysts believe China has deployed 18 to 36 Dongfeng 5 (“East Wind”) ICBMs since the 1980s.