Why Would One Want to Use Nuclear Weapons in Space?
With the launch of Sputnik 1 in 1957, the military application of space as a possible means to attack and defend against an enemy was born. Primarily, this possibility was exploited most readily by the United States and the Soviet Union, at the time embroiled in a bitter Cold War. Both sides looked for any advantage in warfare possible. The fact that a nuclear weapon could be launched from space was highly important. In addition, as satellite technology expanded, the use of nuclear missiles to destroy or in incapacitate communications became of utmost value.
As the space race grew and developed, the threat became even more real. With the development of orbiting space stations, the likelihood of space-based weapons platforms meant that detonations in space and a launch from space to the ground was possible, maybe even probable. There was even a short-lived plan by the United States to send an atomic bomb to the Moon to signify superiority.
Soviet and US Detonations and Their Impact on the Surface
As of 2011, only two nations have detonated nuclear weapons in space: the Soviet Union and the United States. According to historical records supplied by both countries, these tests took place between April 1958 and November 1962. The US conducted 14 publicly-avowed tests during this period, while the USSR released information about seven. Dozens more were attempted by each side, but many of these were conducted in conjunction with the Cuban Missile Crisis, when both countries were in a nuclear standoff over missiles off the coast of the US mainland. The high-altitude nuclear explosions were a form of demonstrating each country's superiority over the other.
Among one of the largest detonations was the Teak test of August 1, 1958. As part of Operation Hardtack I, a series of nuclear tests in the Pacific Ocean, the US exploded a 3.8 megaton warhead 47.7 miles (76.8 km) above the Earth's surface near Johnston Atoll. Following the explosion, debris from the detonation entered the ionosphere, reflecting radio waves back to the surface and preventing long-range communications. This lasted for several hours and affected an area from New Zealand to Hawaii.
A similar incident occurred on July 9, 1962. Codenamed the Starfish Prime test, a 1.4 megaton warhead was detonated 248 miles (roughly 400 km) above the Earth. The resulting explosion was the largest reported by either the US or Soviets. Starfish Prime's electromagnetic pulse blocked out telephones, knocked out streetlights and blocked out other communications links. In addition, bright light was present in the atmosphere for many days as a result of the debris.
What Happens If a Nuke is Exploded in Space?
One of the major concerns with detonating a nuclear weapon in the confines of space is the effects such an explosion would have on personnel orbiting the Earth. According to NASA, these effects would be far different than the impact of a nuclear blast near the surface of the planet. On Earth, the detonation causes pressures of four to ten pounds per square inch. This will destroy most buildings and other bodies in its wake. In addition, the heat level will severely burn any biological material within the radius.
In space, these factors change dramatically. One of the biggest differences is the fact that there is absolutely no blast or thermal radiation. Without air, there is no way for either the pressure or the heat to be produced.
However, since there is no atmosphere, the nuclear radiation will intensify to much higher levels than on the surface. A human body will succumb to death when the radiation levels range between 500 and 5000 roentgens. In space, a 20 kiloton detonation will result in radiation levels eight to 17 times this level. To make the situation more dangerous, no atmosphere also means that it does not dissipate as it would on Earth. The only way the radiation lessens is with distance.
If nuclear weapons are to be used in space for combat purposes, it will mean that sheer radiation attacks will be administered against different warring parties. While there will be a limited or unnecessary need for shielding from the explosive or heat effects of nuclear warfare, some sort of protection against the radiation would be necessary. Otherwise, a single blast will simply kill anything in the affected area.
What the Future Holds
Despite the fact that no nuclear technology has been used thus far against humans is a point of success for Earth. The technology to launch nuclear missiles in space exists and may one day become a reality. Thankfully, through treaties supporting peace and the intense research conducted over the years, the use of these weapons in orbit is, at this time, relegated to the past.
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