| High altitude nuclear explosions have historically | | | | belt, while Cosmos V, Injun I and Telstar suffered |
| been nuclear explosions which take place outside | | | | minor degradation, due to some radiation damage |
| the Earth's atmosphere. Such explosions have | | | | to solar cells, etc.). The radiation dose rate was at |
| been tests of nuclear weapons, used to | | | | least 60 rads/day at four months after Starfish |
| determine the effects of the blast and radiation in | | | | for a well-shielded satellite or manned capsule in a |
| the exoatmospheric environment. | | | | polar circular earth orbit, which caused NASA |
| The only nations to detonate nuclear weapons in | | | | concern with regard to its manned space |
| outer space are the United States and the Soviet | | | | exploration programs. |
| Union. The U.S. program began in 1958, with the | | | | In general, nuclear effects in space (or very high |
| Teak and Orange shots, both 3.8 megatons. | | | | altitudes) have a qualitatively different display. |
| These warheads were initially carried on Redstone | | | | While an atmospheric nuclear explosion has a |
| rockets. Later tests were delivered by Thor | | | | characteristic mushroom-shaped cloud, high-altitude |
| missiles for Operation Dominic I tests, and | | | | and space explosions tend to manifest a spherical |
| modified Lockheed X-17 missiles for the Argus | | | | 'cloud,' reminiscent of other space-based |
| tests. The purpose of the shots was to | | | | explosions until distorted by earth's magnetic field, |
| determine both feasibility of nuclear weapons as | | | | and the charged particles resulting from the blast |
| an anti-ballistic missile defense, as well as a means | | | | can cross hemispheres to create an auroral |
| to defeat satellites and manned orbiting vehicles in | | | | display which has led one filmmaker to |
| space. | | | | characterize these detonations as 'the rainbow |
| As it was realized that nuclear weapons created | | | | bombs'. The visual effects of a high-altitude or |
| an electromagnetic pulse, the potential as an | | | | space-based explosion may last longer than |
| anti-satellite weapon became apparent: in August | | | | atmospheric tests, sometimes in excess of 30 |
| 1958 during Hardtack Teak, the EMP was | | | | minutes. Heat from the Bluegill Triple Prime shot, |
| observed at the Apia Observatory at Samoa to | | | | at an altitude of 31 miles, was felt by personnel |
| be four times more powerful than any created | | | | on the ground at Johnston Atoll, and this test |
| by solar storms, while in July 1962 the Starfish | | | | caused retina burns to two personnel at ground |
| Prime test damaged electronics in Honolulu and | | | | zero who were not wearing their safety goggles. |
| New Zealand approximately 800 miles away), | | | | The Soviets detonated four high-altitude tests in |
| fused 300 street lights on Oahu (Hawaii), set off | | | | 1961 and three in 1962. During the Cuban Missile |
| about 100 burglar alarms, and caused the failure | | | | Crisis in October 1962, both the US and the USSR |
| of a microwave repeating station on Kauai, which | | | | detonated several high-altitude nuclear explosions |
| cut off the sturdy telephone system from the | | | | as a form of saber-rattling. The Soviet tests |
| other Hawaiian islands [1]. The radius for an | | | | were meant to demonstrate their anti-ballistic |
| effective satellite kill for the various prompt | | | | missile defenses which would supposedly protect |
| radiations produced by such a nuclear weapon in | | | | their major cities in the event of a nuclear war. |
| space was determined to be roughly 80 km. | | | | The worst effects of a Russian high altitude test |
| Further testing to this end was carried out, and | | | | occurred on 22 October 1962 (during the Cuban |
| embodied in a Department of Defense program, | | | | missile crisis), in ‘Operation K’ |
| Program 437. | | | | (ABM System A proof tests) when a 300-kt |
| The problems with nuclear weapons carried over | | | | missile-warhead detonated near Dzhezkazgan at |
| to testing and deployment scenarios, however. | | | | 290-km altitude. The EMP fused 570 km of |
| Because of the very large radius associated with | | | | overhead telephone line with a measured current |
| nuclear events, it was nearly impossible to | | | | of 2,500 A, started a fire that burned down the |
| prevent indiscriminate damage to other satellites, | | | | Karaganda power plant, and shut down 1,000-km |
| including one's own satellites. Starfish Prime | | | | of shallow-buried power cables between Aqmola |
| produced an artificial radiation belt in space which | | | | and Almaty. The Partial Test Ban Treaty was |
| soon destroyed three satellites (Ariel, Traac, and | | | | passed the following year, ending atmospheric and |
| Transit 4B all failed after transversing the radiation | | | | exoatmospheric nuclear tests. |