A Thor rocket carrying a W49thermonuclear warhead (designed at Los Alamos Scientific Laboratory) and a Mk. 2 reentry vehicle was launched from Johnston Atoll in the Pacific Ocean, about 900 miles (1,450km) west-southwest of Hawaii. The explosion took place at an altitude of 250 miles (400km), above a point 19 miles (31km) southwest of Johnston Atoll. It had a yield of 1.4Mt (5.9PJ). The explosion was about 10° above the horizon as seen from Hawaii, at 11pm Hawaii time.[1]:3
The Starfish test was one of five high-altitude tests grouped together as Operation Fishbowl within the larger Operation Dominic, a series of tests in 1962 begun in response to the Soviet announcement on August 30, 1961, that they would end a three-year moratorium on testing.[2]
In 1958, the United States had completed six high-altitude nuclear tests that produced many unexpected results and raised many new questions. According to the U.S. Government Project Officer's Interim Report on the Starfish Prime project:[3]
Previous high-altitude nuclear tests: YUCCA, TEAK, and ORANGE, plus the three ARGUS shots were poorly instrumented and hastily executed. Despite thorough studies of the meager data, present models of these bursts are sketchy and tentative. These models are too uncertain to permit extrapolation to other altitudes and yields with any confidence. Thus there is a strong need, not only for better instrumentation, but for further tests covering a range of altitudes and yields.
The Starfish test was originally planned as the second in the Fishbowl series, but the first launch (Bluegill) was lost by the radar tracking equipment and had to be destroyed in flight.[4]:247
The initial Starfish launch attempt on June 20 was also aborted in flight, this time due to failure of the Thor launch vehicle. The Thor missile flew a normal trajectory for 59seconds; then the rocket engine stopped, and the missile began to break apart. The range safety officer ordered the destruction of the missile and warhead. The missile was between 30,000 and 35,000 feet (9,100 and 10,700m) in altitude when it was destroyed. Parts of the missile and some radioactive contamination fell upon Johnston Atoll, nearby Sand Island, and the surrounding ocean.[4]
Explosion
Another view of Starfish Prime through thin cloud, as seen from Honolulu
On July 9, 1962, at 09:00:09 Coordinated Universal Time (11:00:09pm on July 8, 1962, Honolulu time), the Starfish Prime test was detonated at an altitude of 250 miles (400km). The coordinates of the detonation were 16°28′N169°38′W / 16.467°N 169.633°W / 16.467; -169.633.[1]:4 The actual weapon yield came very close to the design yield, which various sources have set at different values in the range of 1.4 to 1.45Mt (5.9 to 6.1PJ). The nuclear warhead detonated 13minutes 41seconds after liftoff of the Thor missile from Johnston Atoll.[5]
Frame of the Starfish Prime Nuclear Test
Starfish Prime caused an electromagnetic pulse (EMP) that was far larger than expected, so much larger that it drove much of the instrumentation off scale, causing great difficulty in getting accurate measurements. The Starfish Prime electromagnetic pulse also made those effects known to the public by causing electrical damage in Hawaii, about 900 miles (1,450km) away from the detonation point, knocking out about 300 streetlights,[1]:5 setting off numerous burglar alarms, and damaging a telephone company microwave link.[6] The EMP damage to the microwave link shut down telephone calls from Kauai to the other Hawaiian Islands.[7]
A total of 27 small rockets were launched from Johnston Atoll to obtain experimental data from the Starfish Prime detonation. In addition, a large number of rocket-borne instruments were launched from Barking Sands, Kauai, in the Hawaiian Islands.[8]
A large number of United States military ships and aircraft were operating in support of Starfish Prime in the Johnston Atoll area and across the nearby North Pacific region.
A few military ships and aircraft were also positioned in the region of the South Pacific Ocean near the Samoan Islands. This location was at the southern end of the magnetic field line of the Earth's magnetic field from the position of the nuclear detonation, an area known as the "southern conjugate region" for the test. An uninvited scientific expeditionary ship from the Soviet Union was stationed near Johnston Atoll for the test, and another Soviet scientific expeditionary ship was in the southern conjugate region near the Samoan Islands.[9]
After the Starfish Prime detonation, bright auroras were observed in the detonation area, as well as in the southern conjugate region on the other side of the equator from the detonation. According to one of the first technical reports:[8]
The visible phenomena due to the burst were widespread and quite intense; a very large area of the Pacific was illuminated by the auroral phenomena, from far south of the south magnetic conjugate area (Tongatapu) through the burst area to far north of the north conjugate area (French Frigate Shoals)... At twilight after the burst, resonant scattering of light from lithium and other debris was observed at Johnston and French Frigate Shoals for many days confirming the long time presence of debris in the atmosphere. An interesting side effect was that the Royal New Zealand Air Force was aided in anti-submarine maneuvers by the light from the bomb.
These auroral effects were partially anticipated by Nicholas Christofilos, a scientist who had earlier worked on the Operation Argus high-altitude nuclear shots.
According to U.S. atomic veteran Cecil R. Coale,[10] some hotels in Hawaii offered "rainbow bomb" parties on their roofs for Starfish Prime, contradicting some reports that the artificial aurora was unexpected.
"A 'Quick Look' at the Technical Results of Starfish Prime" (August 1962) states:[8]
At Kwajalein, 1,400 [nautical] miles [2,600 km; 1,600 mi] to the west, a dense overcast extended the length of the eastern horizon to a height of 5 or 8 degrees. At 0900 GMT a brilliant white flash burned through the clouds rapidly changing to an expanding green ball of irradiance extending into the clear sky above the overcast. From its surface extruded great white fingers, resembling cirro-stratus clouds, which rose to 40 degrees above the horizon in sweeping arcs turning downward toward the poles and disappearing in seconds to be replaced by spectacular concentric cirrus like rings moving out from the blast at tremendous initial velocity, finally stopping when the outermost ring was 50 degrees overhead. They did not disappear but persisted in a state of frozen stillness. All this occurred, I would judge, within 45 seconds. As the purplish light turned to magenta and began to fade at the point of burst, a bright red glow began to develop on the horizon at a direction 50 degrees north of east and simultaneously 50 degrees south of east expanding inward and upward until the whole eastern sky was a dull burning red semicircle 100 degrees north to south and halfway to the zenith obliterating some of the lesser stars. This condition, interspersed with tremendous white rainbows, persisted no less than ninety minutes.
At zero time at Johnston, a white flash occurred, but as soon as one could remove his goggles, no intense light was present. A second after shot time a mottled red disc was observed directly overhead and covered the sky down to about 45 degrees from the zenith. Generally, the red mottled region was more intense on the eastern portions. Along the magnetic north-south line through the burst, a white-yellow streak extended and grew to the north from near zenith. The width of the white streaked region grew from a few degrees at a few seconds to about 5–10 degrees in 30 seconds. Growth of the auroral region to the north was by addition of new lines developing from west to east. The white-yellow auroral streamers receded upward from the horizon to the north and grew to the south and at about 2 minutes the white-yellow bands were still about 10 degrees wide and extended mainly from near zenith to the south. By about two minutes, the red disc region had completed disappearance in the west and was rapidly fading on the eastern portion of the overhead disc. At 400 seconds essentially all major visible phenomena had disappeared except for possibly some faint red glow along the north-south line and on the horizon to the north. No sounds were heard at Johnston Atoll that could be definitely attributed to the detonation.
Strong electromagnetic signals were observed from the burst, as were significant magnetic field disturbances and earth currents.
A 2006 report described the particle and field measurements of the Starfish diamagnetic cavity and the injected beta flux into the artificial radiation belt.[11] These measurements describe the explosion from 0.1milliseconds to 16minutes after the detonation.
After effects
The explosion released roughly 1029 electrons into the Earth's magnetosphere.[12] While some of the energetic beta particles followed the Earth's magnetic field and illuminated the sky, other high-energy electrons became trapped and formed radiation belts around the Earth. The added electrons increased the intensity of electrons within the natural inner Van Allen radiation belt by several orders of magnitude.[12] There was much uncertainty and debate[by whom?] about the composition, magnitude and potential adverse effects from the trapped radiation after the detonation. The weaponeers became quite worried when three satellites in low Earth orbit were disabled. These included TRAAC and Transit 4B.[13] The half-life of the energetic electrons was only a few days. At the time it was not known that solar and cosmic particle fluxes varied by a factor of 10, and energies could exceed 1MeV (0.16pJ). In the months that followed, these man-made radiation belts eventually caused six or more satellites to fail,[14] as radiation damaged their solar arrays or electronics, including the first commercial relay communication satellite, Telstar, as well as the United Kingdom's first satellite, Ariel 1.[15] Detectors on Telstar, TRAAC, Injun, and Ariel 1 were used to measure distribution of the radiation produced by the tests.[16]
In 1963, it was reported that Starfish Prime had created a belt of MeV electrons.[17] In 1968, it was reported that some Starfish electrons had remained in the atmosphere for 5 years.[18]
As an explosion in outer space, the fallout from Starfish Prime was less than other above ground tests. Estimates for its health impacts and excess deaths, including from thyroid cancer, are hard to find, but the overall excess death impact of thousands of above-ground tests have likely amounted to between 10,000 and 100,000. A year later, the US and USSR signed the Partial Nuclear Test Ban Treaty, which banned all above-ground nuclear testing. France and China continued above-ground tests for a few more decades.[19]
Resulting scientific discoveries
The Starfish bomb contained 109Cd as a tracer, which helped work out the seasonal mixing rate of polar and tropical air masses.[20]
Johnston Atoll is an unincorporated territory of the United States, under the jurisdiction of the United States Air Force (USAF). The island is closed to public entry, and limited access for management needs is only granted by letter of authorization from the USAF. A special use permit is also required from the United States Fish and Wildlife Service (USFWS) to access the island by boat or enter the waters surrounding the island, which are designated as a National Wildlife Refuge and part of the Pacific Remote Islands Marine National Monument. The Johnston Atoll National Wildlife Refuge extends from the shore out to 12 nautical miles, continuing as part of the National Wildlife Refuge System out to 200 nautical miles. The Pacific Remote Islands Marine National Monument extends from the shore out to 200 nautical miles.
A nuclear electromagnetic pulse is a burst of electromagnetic radiation created by a nuclear explosion. The resulting rapidly varying electric and magnetic fields may couple with electrical and electronic systems to produce damaging current and voltage surges. The specific characteristics of a particular nuclear EMP event vary according to a number of factors, the most important of which is the altitude of the detonation.
Operation Argus was a series of United States low-yield, high-altitude nuclear weapons tests and missile tests secretly conducted from 27 August to 9 September 1958 over the South Atlantic Ocean. The tests were performed by the Defense Nuclear Agency.
The effects of a nuclear explosion on its immediate vicinity are typically much more destructive and multifaceted than those caused by conventional explosives. In most cases, the energy released from a nuclear weapon detonated within the lower atmosphere can be approximately divided into four basic categories:
A mushroom cloud is a distinctive mushroom-shaped flammagenitus cloud of debris, smoke, and usually condensed water vapor resulting from a large explosion. The effect is most commonly associated with a nuclear explosion, but any sufficiently energetic detonation or deflagration will produce the same effect. They can be caused by powerful conventional weapons, like thermobaric weapons such as the ATBIP and GBU-43/B MOAB. Some volcanic eruptions and impact events can produce natural mushroom clouds.
Operation Hardtack I was a series of 35 nuclear tests conducted by the United States from April 28 to August 18 in 1958 at the Pacific Proving Grounds. At the time of testing, the Operation Hardtack I test series included more nuclear detonations than the total of prior nuclear explosions in the Pacific Ocean. These tests followed the Project 58/58A series, which occurred from 1957 December 6 to 1958, March 14, and preceded the Operation Argus series, which took place in 1958 from August 27 to September 6.
Elugelab, or Elugelap, was an island, part of the Enewetak Atoll in the Marshall Islands. It was destroyed by the world's first true hydrogen bomb test on 1 November 1952, a test which was codenamed shot "Mike" of Operation Ivy. Prior to being destroyed, the island was described as "just another small naked island of the atoll".
Operation Fishbowl was a series of high-altitude nuclear tests in 1962 that were carried out by the United States as a part of the larger Operation Dominic nuclear test program.
The following is a chronology of discoveries concerning the magnetosphere.
The Christofilos effect, sometimes known as the Argus effect, refers to the entrapment of electrons from nuclear weapons in the Earth's magnetic field. It was first predicted in 1957 by Nicholas Christofilos, who suggested the effect had defensive potential in a nuclear war, with so many beta particles becoming trapped that warheads flying through the region would experience huge electrical currents that would destroy their trigger electronics. The concept that a few friendly warheads could disrupt an enemy attack was so promising that a series of new nuclear tests was rushed into the US schedule before a testing moratorium came into effect in late 1958. These tests demonstrated that the effect was not nearly as strong as predicted, and not enough to damage a warhead. However, the effect is strong enough to be used to black out radar systems and disable satellites.
High-altitude nuclear explosions are the result of nuclear weapons testing within the upper layers of the Earth's atmosphere and in outer space. Several such tests were performed at high altitudes by the United States and the Soviet Union between 1958 and 1962.
Program 437 was the second anti-satellite weapons program of the U.S. military. The US anti-satellite weapons program began development in the early 1960s and was officially discontinued on 1 April 1975. Program 437 was approved for development by U.S. Secretary of Defense Robert McNamara on November 20, 1962, after a series of tests involving high altitude nuclear explosions. The program's facilities were located on Johnston Island, an isolated island in the north central Pacific Ocean.
HARDTACK-Teak was an exoatmospheric high altitude nuclear weapon test performed during Operation Newsreel. It was launched from Johnston Atoll on a Redstone missile. On 1 August 1958, the 3.88 Mt (16.2 PJ) shot detonated at an altitude of 76.8 km.
The Soviet Union's K project nuclear test series was a group of five nuclear tests conducted in 1961–1962. These tests followed the 1961 Soviet nuclear tests series and preceded the 1962 Soviet nuclear tests series.
Operation Dominic was a series of 31 nuclear test explosions ("shots") with a 38.1 Mt (159 PJ) total yield conducted in 1962 by the United States in the Pacific. This test series was scheduled quickly, in order to respond in kind to the Soviet resumption of testing after the tacit 1958–1961 test moratorium. Most of these shots were conducted with free fall bombs dropped from B-52 bomber aircraft. Twenty of these shots were to test new weapons designs; six to test weapons effects; and several shots to confirm the reliability of existing weapons. The Thor missile was also used to lift warheads into near-space to conduct high-altitude nuclear explosion tests; these shots were collectively called Operation Fishbowl.
Nuclear blackout, also known as fireball blackout or radar blackout, is an effect caused by explosions of nuclear weapons that disturbs radio communications and causes radar systems to be blacked out or heavily refracted so they can no longer be used for accurate tracking and guidance. Within the atmosphere, the effect is caused by the large volume of ionized air created by the energy of the explosion, while above the atmosphere it is due to the action of high-energy beta particles released from the decaying bomb debris. At high altitudes, the effect can spread over large areas, hundreds of kilometers. The effect slowly fades as the fireball dissipates.
Explorer 15, also called EPE-C or Energetic Particles Explorer-C, was a NASA satellite launched as part of the Explorer program. Explorer 15 was launched on 27 October 1962, at Cape Canaveral Air Force Station, Florida, United States, with a Thor-Delta A.
STARAD was a radiation-monitoring satellite used to track the artificial radiation belt created by the Starfish Prime high-altitude nuclear test.
↑ "Operation Dominic: 1962 – Christmas Island, Johnston Island, Central Pacific". nuclearweaponarchive.org. January 3, 2005. Archived from the original on August 6, 2020. Retrieved September 15, 2020. The Soviet Union had abrogated the 34 month old de facto nuclear testing moratorium on 1 September 1961, by initiating an unprecedented series of atmospheric nuclear tests.
↑ Loadabrand, Ray L.; Dolphin, Lambert T. (August 1, 1962). "Chapter 1"(PDF). Project Officer's Interim Report: Starfish Prime (Report). Field Command, Defense Atomic Support Agency. p.2. DA 49-146-XZ-137. Archived from the original(PDF) on January 17, 2019. Retrieved September 15, 2020. Previous high-altitude nuclear tests: TEAK, ORANGE, and YUCCA, plus the three ARGUS shots were poorly instrumented and hastily executed. Despite thorough studies of the meager data, present models of these bursts are sketchy and tentative. These models are too uncertain to permit extrapolation to other altitudes and yields with any confidence. Thus there is a strong need, not only for better instrumentation, but for further tests covering a range of altitudes and yields.
1 2 Berkhouse, L.; Davis, S. E.; Gladeck, F. R.; Hallowell, J. H.; Jones, C. B.; etal. (February 1, 1983). "Chapter 7 – Fishbowl – High-Altitude Events"(PDF). Operation Dominic I–1962. Defense Threat Reduction Agency. dtra.mil (Report). pp.228–229. Archived from the original(PDF) on August 13, 2020. Retrieved September 15, 2020. A substantial amount of debris fell on and in the water around Johnston Island. Navy Explosive Ordance Disposal and Underwater Demolition Team swimmers spent 2 weeks recovering debris from the lagoon waters around the island. They recovered approximately 250 pieces of the system, some of which were plutonium-contaminated.
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