High-altitude nuclear explosions are the result of nuclear weapons testing. Nuclear weapons tests are experiments carried out to determine the effectiveness, yield, and explosive capability of nuclear weapons. Throughout the twentieth century, most nations that developed nuclear weapons tested them. During the heart of the Cold War, the United States of America and the former Soviet Union launched and detonated a combined total of over twenty thermonuclear weapons in the upper-atmosphere and near space region of Earth in an effort to test the effects of launching an offense as well as countering an offense.
Testing nuclear weapons (high-altitude nuclear explosions) can yield information about how the weapons work, as well as how the weapons behave under various conditions and how personnel, structures, and equipment behave when subjected to nuclear explosions. Nuclear testing has often been used as an indicator of scientific and military strength, and many tests have been overtly political in their intention; most nuclear weapons states publicly declared their nuclear status by means of a nuclear test. A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission bomb) or from a combination of fission and fusion reactions (thermonuclear bomb). Both bomb types release large quantities of energy from relatively small amounts of matter.
Several such tests (high-altitude nuclear explosions) were performed at high altitudes by the United States of America and the Soviet Union between 1958 and 1962. The familiar immediate effects of low-altitude nuclear explosions are flash, blast, and prompt radiation. Effects are significantly different for explosions above most of the atmosphere. Since blast is the shock wave transmitted through air, this is attenuated with height and is absent for explosions beyond the atmosphere. Flash is the visible and infrared light pulse from the fireball formed from heated air. With higher altitude, the fireball formation is significantly altered with consequent effects on flash. Prompt radiation includes ionising radiation from the nuclear reactions in the warhead and decay of fission products left by the explosion. These radiations, particularly neutron radiation, are significantly attenuated by the atmosphere for low altitude bursts. For explosions above most of the atmosphere, ranges of prompt radiation effects are greater than for atmospheric bursts.
Operation Hardtack I
Operation Hardtack I was, when speaking about high-altitude nuclear explosions, a series of thirty-five nuclear tests conducted by the United States of America from April 28 to August 18 in 1958 at the Pacific Proving Grounds (a number of sites in the Marshall Islands and a few other sites in the Pacific Ocean at which the United States of America conducted nuclear testing between 1946 and 1962).
HARDTACK-Teak was an exoatmospheric (pertaining to, or occurring in the nearby region of space outside the Earth’s atmosphere) high altitude nuclear weapon test performed during Operation Hardtack I. It was launched from Johnston Island on a Redstone missile. On August 1, 1958, it detonated at an altitude of seventy-seven kilometres.
Operation Argus was a series of United States of America low-yield, high-atmosphere nuclear weapons tests and missile tests secretly conducted during August and September 1958 over the South Atlantic Ocean. The ARGUS tests took eleven days from start to finish with the first launch on August 27 and the final launch on September 6. They were performed by the Defense Nuclear Agency, in conjunction with the Explorer 4 space mission.
The tests were proposed as a means to verify the Christofilos effect, which argued that high-altitude nuclear detonations would create a radiation belt in the extreme upper regions of the Earth’s atmosphere. Such belts would be similar in effect to the Van Allen radiation belts: “Such radiation belts were viewed as having possible tactical use in war, including degradation of radio and radar transmissions, damage or destruction of the arming and fuzzing mechanisms of ICBM warheads, and endangering the crews of orbiting space vehicles that might enter the belt”.
The Christofilos effect refers to the entrapment of charged particles along magnetic lines of force that was first predicted in 1957 by the Greek physicist Nicholas Christofilos (December 16, 1916 – September 24, 1972). Christofilos suggested the effect had defensive potential in a nuclear war, with so many beta particles (electrons) becoming trapped that warheads flying through the region would see electrical currents so great that their trigger electronics would be damaged. 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 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 radars and disable satellites.
The Soviets detonated four high-altitude tests in 1961. Kapustin Yar was a Russian rocket launch and development site in Astrakhan Oblast, between Volgograd and Astrakhan. It was established by the Soviet Union on May 13, 1946 and in the beginning used technology, material and scientific support from defeated Germany. Numerous launches of test rockets for the Russian military were carried out at the site, as well as satellite and sounding rocket launches.
Starfish Prime and high-altitude nuclear explosions
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. Flight-test vehicles were designed and manufactured by Avco Corporation. The Operation Fishbowl nuclear tests were originally planned to be completed during the first half of 1962 with three tests named Bluegill, Starfish and Urraca.
Starfish Prime was a July 9, 1962 high-altitude nuclear test conducted by the United States of America, a joint effort of the Atomic Energy Commission (AEC) and the Defense Atomic Support Agency. It was launched from Johnston Island, and was the largest nuclear test conducted in outer space and one of five conducted by the United States of America in outer space. A Thor rocket (the first operational ballistic missile deployed by the U.S. Air Force) carrying a W49 (an American thermonuclear warhead, used on the Thor, Atlas, Jupiter, and Titan I ballistic missile systems) thermonuclear warhead (manufactured by Los Alamos Scientific Laboratory) and a Mk. 2 re-entry vehicle was launched from Johnston Island in the Pacific Ocean, about one thousand five-hundred kilometres west-southwest of Hawaii. The explosion took place at an altitude of four-hundred kilometres, above a point thirty kilometres southwest of Johnston Island. It produced a yield equivalent to one and a half megatons of TNT.
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. In 1958 the United States had completed six high-altitude nuclear tests, but the high-altitude tests of that year produced many unexpected results and raised many new questions.
On July 9, 1962, at 09:00:09 Coordinated Universal Time (the primary time standard by which the world regulates clocks and time), the Starfish Prime test was detonated at an altitude of four hundred kilometres. Starfish Prime caused an electromagnetic pulse (EMP), which 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 one thousand and five hundred kilometres away from the detonation point, knocking out about three hundred streetlights, setting off numerous burglar alarms and damaging a telephone company microwave link.
Soviet Project K nuclear tests – High-altitude nuclear explosions
The Soviet Union’s K project nuclear test series were all high altitude tests fired by missiles from the Kapustin Yar launch site in Russia across central Kazakhstan toward the Sary Shagan test range. The worst effects of a Soviet high-altitude test occurred on October 22, 1962 (during the Cuban missile crisis) when a three hundred kilotons missile-warhead detonated near Jezkazgan at an altitude of three hundred kilometres. Although the weapons used in the K Project were much smaller (up to three hundred kilotons) than the United States of America’ Starfish Prime test of 1962, the damage caused by the resulting EMP was much greater because the K Project tests were done over a large populated land mass, and at a location where the Earth’s magnetic field was greater.
The legality of high-altitude nuclear explosions
Sputnik 1 was launched on October 14, 1957 and proceeded to orbit the Earth blithely unconcerned with the political boundaries below. It was apparent that space activities had international implications. Concerning the United Nations, the question of space activities was first raised in 1957 in the context of the debate on disarmament. In 1958, the Question on the Peaceful Uses of Outer Space was placed on the agenda of the General Assembly. The thirteenth session of the General Assembly, held in 1958, provided a forum for the debate on Questions of the Peaceful Use of Outer Space. During this session, the term peaceful was used as an antonym to military. Sweden appealed to fellow Member States to any military use whatsoever and the Soviet Union put forward a proposal to ban the use of outer space for military purposes. The General Assembly adopted resolution 1348 (XIII), which recognized the common aim of humankind that outer space should be used for peaceful purposes only.
The General Assembly stated that it wished to avoid the extension of present national rivalries into the field of outer space, that the exploration and exploitation of outer space shall be done for the benefit of mankind, considered that such co-operation will promote mutual understanding and the strengthening of friendly relations among people. To ensure those objectives, the 792nd plenary meeting decided to establish an ad hoc (Latin, For this, for this special purpose; Committee formed for a specific task or objective) Committee on the Peaceful Uses of Outer Space composed of the representatives of Argentina, Australia, Belgium, Brazil, Canada, Czechoslovakia, France, India, Iran, Italy, Japan, Mexico, Poland, Sweden, the Union of Soviet Socialist Republics, the United Arab Republic, the United Kingdom of Great Britain and Northern Ireland and the United States of America, which would only officially truly start with the 1472 (XIV)’s resolution – December 12, 1959 – on INTERNATIONAL CO-OPERATION IN THE PEACEFUL USES OF OUTER SPACE.
In 1959, the Committee would be launched by twenty-four Member States. It has considerably expanded since then and is today one of the largest United Nations Committees. In addition to the Member States, several International Organisations, both governmental and non-governmental, have an observer status in the COPUOS and its subcommittees. In particular, the European Union is an ad hoc observer.
The Committee on the Peaceful Uses of Outer Space (COPUOS) was set up by the General Assembly in 1959 to govern the exploration and use of space for the benefit of all humanity: for peace, security and development. The Committee was tasked with reviewing international cooperation in peaceful uses of outer space, studying space-related activities that could be undertaken by the United Nations, encouraging space research programmes, and studying legal problems arising from the exploration of outer space. The Committee was instrumental in the creation of the five treaties and five principles of outer space. International cooperation in space exploration and the use of space technology applications to meet global development goals are discussed in the Committee every year. Owing to rapid advances in space technology, the space agenda is constantly evolving. The Committee provides a unique platform at the global level to monitor and discuss these developments. The Committee has two subsidiary bodies: the Scientific and Technical Subcommittee, and the Legal Subcommittee, both established in 1961.
Its first session was held in May and June of 1959 and produced a useful account of current activities in outer space. Some of the suggestions of this session provided a basis for follow-up action later in the United Nations. However, only thirteen of the eighteen countries on the Committee attended this session. Czechoslovakia, Poland and the Soviet Union refused to attend, expressing dissatisfaction with the composition of the Committee. India and the United Arab Republic also did not attend. There is widespread interest in the United Nations in fostering international co-operation in outer space for two basic reasons: first, to maximize co-operation between the two major space Powers despite their political differences; and second, to encourage the increased peaceful uses of outer space to benefit all countries irrespective of the stage of their economic or scientific development. Countries realize that activities going forward in outer space – satellites helping to forecast the weather, to increase communications, to improve navigational conditions, to test for radioactivity, to do basic research – will all make their impact on everyone on this earth with increasing force.
If the Soviet Union was able on October 4, 1957 to orbit Sputnik 1, the first space object, it meant that it would also be able to use intercontinental ballistic missiles (an intercontinental ballistic missile or ICBM, is a guided ballistic missile with a minimum range of five thousand five hundred kilometres primarily designed for nuclear weapons delivery – delivering one or more thermonuclear warheads) against its adversaries, in particular the United States of America. The question of the militarization of outer space is a very delicate issue, the subject being highly strategic, and States not easily agreeing on it, often leaving room for further misunderstandings. Since a resolution of the United Nations General Assembly of December 13, 1958, it was desired to see outer space used exclusively for peaceful purposes. The General Assembly stated that it wished to avoid the extension of present national rivalries into the field of outer space, that the exploration and exploitation of outer space shall be done for the benefit of mankind, considered that such co-operation will promote mutual understanding and the strengthening of friendly relations among people. The Partial Test Ban Treaty, signed on August 5, 1963, also prohibits nuclear weapons testing in the atmosphere, beyond its limits, including outer space, or underwater, including territorial waters or high seas. This text has the merit of enacting prohibitions that extend as much to areas under the jurisdiction of States as to spaces removed from the sovereignty of States. It is also important to mention that resolution 1884 (XVIII), calling upon States to refrain from placing in orbit around the Earth any objects carrying nuclear weapons or any other kinds of weapons of mass destruction or from installing such weapons on celestial bodies, was adopted unanimously by the United Nations General Assembly on October 17, 1963.
The Partial Test Ban Treaty (PTBT)
The Partial Test Ban Treaty (PTBT) is the abbreviated name of the 1963 Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water, which prohibited all test detonations of nuclear weapons except for those conducted underground. The PTBT was signed by the governments of the Soviet Union, United Kingdom, and United States of America in Moscow on August 5, 1963 before being opened for signature by other countries. The treaty formally went into effect on October 10, 1963. Since then, one hundred and twenty other states have become party to the treaty. Ten states have signed but not ratified the treaty. Article I states that “Each of the Parties to this Treaty undertakes to prohibit, to prevent, and not to carry out any nuclear weapon test explosion, or any other nuclear explosion, at any place under its jurisdiction or control: (b) in any other environment if such explosion causes radioactive debris to be present outside the territorial limits of the State under whose jurisdiction or control such explosion is conducted. It is understood in this connection that the provisions of this subparagraph are without prejudice to the conclusion of a Treaty resulting in the permanent banning of all nuclear test explosions, including all such explosions underground, the conclusion of which, as the Parties have stated in the Preamble to this Treaty, they seek to achieve; (a) in the atmosphere; beyond its limits, including outer space; or under water, including territorial waters or high seas”.
Space Laws and high-altitude nuclear explosions
Article IV of the 1967 Treaty distinguishes the legal regime for the whole of outer space and special limits concerning the Moon and other celestial bodies. It states that “States Parties to the Treaty undertake not to place in orbit around the Earth any objects carrying nuclear weapons or any other kinds of weapons of mass destruction, install such weapons on celestial bodies, or station such weapons in outer space in any other manner. The Moon and other celestial bodies shall be used by all States Parties to the Treaty exclusively for peaceful purposes. The establishment of military bases, installations and fortifications, the testing of any type of weapons and the conduct of military manoeuvres on celestial bodies shall be forbidden. The use of military personnel for scientific research or for any other peaceful purposes shall not be prohibited. The use of any equipment or facility necessary for peaceful exploration of the Moon and other celestial bodies shall also not be prohibited”. It refers to a total demilitarization of outer space and prohibits weapons of mass destruction, that is to say, atomic, bacteriological, chemical or equivalent effect. We can also think of environmental modification techniques for military or hostile purposes, as envisaged since the Convention of May 18, 1977, which prohibits the use of such weapons. The Environmental Modification Convention (ENMOD), formally the Convention on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques, is an international treaty prohibiting the military or other hostile use of environmental modification techniques having widespread, long-lasting or severe effects. It opened for signature on May 18, 1977 in Geneva and entered into force on October 5, 1978. The Convention bans weather warfare, which is the use of weather modification techniques, such as cloud seeding, for the purposes of inducing damage or destruction. The Convention on Biological Diversity of 2010 would also ban some forms of weather modification or geoengineering.
This ban on certain armaments, particularly on Earth orbits, is obviously one of the most important for security on Earth. Recall that the Treaty of Outer Space (1967) was adopted at a time when arms limitation agreements were at the heart of diplomatic concerns, especially those of the two superpowers (The Treaty of Tlatelolco, signed on February 14, 1967, is the conventional name given to the Treaty for the Prohibition of Nuclear Weapons in Latin America and the Caribbean; the Treaty on the Non-Proliferation of Nuclear Weapons, commonly known as the Non-Proliferation Treaty or NPT, signed on July 1, 1968, is an international treaty whose objective is to prevent the spread of nuclear weapons and weapons technology, to promote cooperation in the peaceful uses of nuclear energy, and to further the goal of achieving nuclear disarmament and general and complete disarmament; the Strategic Arms Limitation Talks (SALT) were two rounds of bilateral conferences and corresponding international treaties involving the United States of America and the Soviet Union, the Cold War superpowers, on the issue of arms control. The two rounds of talks and agreements were SALT I and SALT II and negotiations commenced in Helsinki, Finland, in November 1969). The total demilitarization of the Moon and celestial bodies is also provided for in the Agreement Governing the Activities of States on the Moon and Other Celestial Bodies (entered into force on July 11, 1984).
Article 3 of the Moon Agreement of 1979 states that “States Parties shall not place in orbit around or other trajectory to or around the Moon objects carrying nuclear weapons or any other kinds of weapons of mass destruction or place or use such weapons on or in the Moon. The establishment of military bases, installations and fortifications, the testing of any type of weapons and the conduct of military manoeuvres on the Moon shall be forbidden. The use of military personnel for scientific research or for any other peaceful purposes shall not be prohibited. The use of any equipment or facility necessary for peaceful exploration and use of the Moon shall also not be prohibited”.
Concerning high-altitude nuclear explosions, there are questions about the interpretation of the term peaceful: either non-military (broad interpretation) or non-aggressive (narrow interpretation). The United States of America prefers the narrow interpretation and constructs its argument by explaining that it is necessary to retain the right of self-defence, as expressed both in customary law and in Article 51 of the Charter of the United Nations. Chapter VII, Article 51 of the Charter of the United Nations concerning “Action with respect to Threats to the Peace, Breaches of the Peace, and Acts of Aggression” states that “Nothing in the present Charter shall impair the inherent right of individual or collective self-defence if an armed attack occurs against a Member of the United Nations, until the Security Council has taken measures necessary to maintain international peace and security. Measures taken by Members in the exercise of this right of self-defence shall be immediately reported to the Security Council and shall not in any way affect the authority and responsibility of the Security Council under the present Charter to take at any time such action as it deems necessary in order to maintain or restore international peace and security”.
Speaking about high-altitude nuclear explosions, the National Aeronautics and Space Administration (NASA) Act of 1958 also refers to the peaceful purposes of research and outer space, stating that “The Congress hereby declares that it is the policy of the United States that activities in space should be devoted to peaceful purposes for the benefit of all mankind”. The United States of America has always considered the action of reconnaissance satellites (a reconnaissance satellite or intelligence satellite, commonly, although unofficially, referred to as a spy satellite, is an Earth observation satellite or communications satellite deployed for military or intelligence applications) to be both military and peaceful. The Soviet Union, for its part, quickly defended the idea that certain activities are prohibited, even for the State acting under conditions of self-defence, based for example on the Geneva Protocol of 1925 on the use of biological weapons (the Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous or other Gases, and of Bacteriological Methods of Warfare, usually called the Geneva Protocol, is a treaty prohibiting the use of chemical and biological weapons in international armed conflicts. It was signed at Geneva on June 17, 1925 and entered into force on February 8, 1928. It was registered in League of Nations Treaty Series on September 7, 1929), the 1972 Convention on the Prohibition of the Manufacture, Stockpiling and Use of Bacteriological and Toxin Weapons (the Convention on the Prohibition of the Development, Production and Stockpiling of Bacteriological and Toxin Weapons and on their Destruction, usually referred to as the Biological Weapons Convention, was the first multilateral disarmament treaty banning the production of an entire category of weapons. The Convention was the result of prolonged efforts by the international community to establish a new instrument that would supplement the 1925 Geneva Protocol. The Geneva Protocol prohibits use but not possession or development of chemical and biological weapons) or the Environmental Modification Convention of May 18, 1977 on Environmental Changes for hostile purposes. The Soviet Union has also come to recognize the peacebuilding function of reconnaissance satellites.
To summarise on high-altitude nuclear explosions, all areas of outer space are devoid of certain weapons, in this case weapons of mass destruction, whether for storage, experimentation or even more use; on the other hand, certain areas, in this case the Moon and the celestial bodies, generally exclude all military activity: all weapons are prohibited in certain areas and certain weapons are prohibited in all zones. This conclusion makes it possible to develop or envisage certain military activities in outer space without the right being able to give an unambiguous answer to the question of the lawfulness of these activities. That is what we can say about high-altitude nuclear explosions.