Just as the world was reeling from the Cuban missile crisis when it had come closer than ever to a nuclear conflict between the US and Soviet union, both the US and the Soviets launched high altitude nuclear tests at the edge of space, one of 9 such tests within a 2 week period at one of the most dangerous times in modern history.
These tests had been run since 1958 and created effects never seen before, so just what were both sides up to and why was so important that nukes needed to be tested in space in the first place.
For many years before the space age it was speculated that the Northern and Southern lights or Auroras where caused by charged particles emitted from the sun and trapped by the earths magnetic field.
In 1957, a secret report handed to the US government by Nicholas Christofilos a Greek physicist working at the Lawrence Livermore National Laboratory said that if you could inject high energy electrons created by a nuclear blast into the lower parts of the parts of the earths magnetic field, it would create an electron shell of radiation that would spread around the earth that could be strong enough to induce high currents into the electronics of any missile flying through it and damage or disable them.
He also stated that because of the way the charged particles travelled in a spiral like way along the lines magnetic force bouncing from one end of the field line to another at almost the speed of light, they would create a large amount of electronic noise at boths end of the field lines in the frequency range that would blind the early warning radar systems. It was also thought that if this electron shield was thick enough it would heat up a missile travelling through it and cause it to burn up in space.
This report came at a crucial time for the US as it was developing it’s first true ICBM’s and if any of these assumptions were correct it could have a major impact on how the could be used.
It could also be used as a shield, by exploding a few nuclear weapons in the Pacific it could provide a blanket covering the US. Conversely, by picking the correct field line in the southern Indian ocean the other end would be in the Soviet Union, detonating a device into the magnetic field line would almost instantly black out radars at the other end with the effect lasting many minutes enough to render Anti-ballistic missiles useless.
In 1958 both the US Explorer 1 satellite and the Soviet Sputnik 2 confirmed that large naturally occurring belts of radiation consisting of trapped charged particles did indeed exist around the earth, these later became known as the Van Allen Belts after the US project leader Dr James Van Allen.
The US needed to move quickly so it added three high altitude tests to Operation Hardtack which was to be the biggest test of nuclear weapons so far with 35 tests in the Pacific proving grounds. The three high altitude tests were code named Yucca, Teak and Orange.
Yucca was the first and consisted of a 1.7kiloton device launched with a balloon from an Aircraft carrier to a height of 26.2 km or 86,000 ft. The main point of this test was to see what effect the EMP or ElectroMagnetic Pulse which was generated by a nuclear explosion would have on electronic devices. The balloon also carried 5 canisters which were dropped just before the detonation and collected data but due to equipment issues on the ship none of this was recorded.
The following test, Teak was much bigger and was originally it was going to be launched from Bikini Atoll but because all the high altitude tests were to be at night to best see the effects, it was though it might damage peoples eyes living on nearby Atolls so the test was moved 2760km east to Johnston Island.
The device was launched on a Redstone missile with a yield of 3.8 megaton and detonated at an altitude of 76.8km about 251,000 ft. It was supposed to detonate 10km south of the island but due to an error in the missile programming it detonated directly above.
Even from 76km away it turned night into day. Ground crew had to run for shelter in the shade and some said they received a mild sunburn from the thermal radiation.
The blast from a space-based test doesn’t have the classic mushroom shape as those on the ground.
But the biggest effect was to the radio communications, the blast caused a radio backout which covered much of the pacific and lasted up to 9 hours in places cutting communications with Australia, New Zealand and Hawaii and knocking out power grids in O‘ahu, Hawaii.
The fission debris from the blast caused the disruption of the ionospheres ability to reflect radio waves which severely affected HF radio communications including for aircraft in the area. The detonation was seen 2000km away in Hawaii and the red afterglow from the blast was visible for 30 minutes in the sky. In Samoa some 3200km to the south there were the most vivid auroral displays ever seen.
The final test, Orange was also a 3.8 megaton device but at an altitude of 43km about 141,000 ft. Although the blast was the same size yield, the effects were not as pronounced, the afterglow lasted about 5 minutes and although communications were affected for a short time it was to a much lesser extent than the Teak blast showing that the altitude of the blast was a major influence on the disruption it caused.
Within a couple of weeks of operation Hardtack, a new set of secret tests were performed in the South Atlantic at a point where the earth’s magnetic field dips to its lowest point, also known as the South Atlantic Anomaly.
The Operation was called Argos and contested of 9 ships and over 4500 personal. The object was to test Christofilos’s theory that you could create a new artificial radiation belt. This would be a more controlled set of three tests, each with a low yield 1.7kiloton device but launched to three different altitudes of 177km, 305km and 793km to see how the effects changed with altitude. It was also to be done in conjunction with the Explorer 4 satellite, rocket, aircraft and ground stations around the world and all in secret though it was leaked a year later, it wasn’t fully declassified until 1982.
The Argos tests did indeed prove Christofilos’s theory was mostly correct. It created an artificial radiation belt that lasted for several weeks and reduced the effectiveness radar signals within the electron shell. It also showed that you would need a much larger injection of fission fragments to create an electron shell that could disable missiles in flight.
In the meant time concern about the proliferation of nuclear tests on all sides and the effect on the environment led to the moratorium of 1958 which banned nuclear tests. This lasted until 1961 when the growing mistrust between the US and Soviets led to it was abandoned with the soviets shortly afterwards detonating the largest ever nuclear device, the 50 megaton Tsar bomba.
The US response was the hastily arranged operation Dominic, again in the Pacific. Within this test were a subset of tests called operation Fishbowl to further test high altitude nuclear devices and their effects. This was deemed necessary because the previous two operations were hastily executed and poorly instrumented leading the data being insufficient and not of a high enough quality to extrapolate the results to higher altitudes and bomb yields.
Operation fishbowl had three main objectives to look at, the EMP pulse and its effect related to altitude, the auroras that would instantly appear many thousands of miles away in the opposite hemisphere and the radio blackouts.
Again Johnston island was used as the base for the launches and after a couple of launch failures Starfish Prime was the first successful test with a 1.4 megaton explosion at 400 km.
The EMP created was much larger than expected and sent most of the instruments off the scale which greatly limited they data collected. It also blew out 300 street lights, set off burglar alarms and damaged a telephone microwave link in Hawaii 2000km away.
After the explosion bright auroras were seen at the ends of the magnetic field lines around Samoa in the south pacific and northern Hawaii in the northern Pacific, an area covering a large portion of the Pacific over 5000km apart. This confirmed that beta particles were travelling back and forth along the magnetic fields lines and created the auroras where they came down it meet the atmosphere.
The radiation belt of trapped charged particles created by Starfish Prime persisted for many months and was directly responsible for the failure of 9 satellites as they passed through it over following days and weeks including Telstar 1 the world’s first commercial telecommunication satellite.
Due of the largely unexpected scale of the effects caused by Starfish Prime, the next test Urraca, which was to be a 1 megaton device at 1000km was cancelled because of the fear that it would destroy many more satellites.
Things came to a halt after a valve failed causing a fuel leak on the Thor rocket of the Bluegill prime test. With the rocket in flames on the launchpad the range officer sent a destruct command which destroyed not only the rocket but most of the launchpad and caused the warhead to explode but not detonate. This spread the radioactive core over the launch area requiring it to be decontaminated before the pad could be rebuilt.
Meanwhile in the Soviet Union they were conducting their own high altitude tests at Karagandy in Kazakhstan. The devices were 300 kiloton and exploded at an altitude of 290km. For the test, a 570 km section of telephone lines in the area was instrumented to see the effect of the EMP. When the device was detonated it burned out the entire length of the telephone line with currents of 1500 to 3400 amps being recorded. It also caused the destruction of the Karaganda power station and shut down 1000km of shallow buried power cabling.
After the fall of the soviet union, scientists from both sides unofficially sheared data and found that the Soviet tests had a much greater EMP effect due to the stronger magnetic field in the area and it was much more populated with more infrastructure.
On the 1st of November 1962 the US carried out the 400 kiloton Kingfish test at 80km high and on the same day the Soviets carried out a 300 kiloton test at 59km, both of these just two 2 days after the Cuban missile crisis came to an end.
The US’s final test called Tightrope was carried out on the 3rd of November 1962. In the end both sides came to the conclusion that testing nuclear devices in space was just too indiscriminate and wide ranging and could cause as much damage to their own space hardware, early warning systems and even manned missions as to the other sides.
With the reintroduction of the test ban treaty of 1963, space based testing was banned with the possible exception of the Vela incident in the south Atlantic in 1979 when a characteristic double flash of a nuclear detonation was picked up by a retired but still functional Vela Hotel satellite, one which was designed to look for breaches of the nuclear test ban treaty.
Although no one has admitted responsibility, it was believed from the available evidence that it was a small device in the range of 3 kilotons, possibly a neutron bomb being secretly tested in the upper atmosphere by either the Israelis or South Africans or the two working together.
So what do you think of the use of space to test nuclear weapons even though they did reveal a great deal about the naturally occurring Van Allen belts and space weather in general, let me know in the comments, so for I’d just like to say thanks for watching and please check out some of our other videos and don’t forget to subscribe, thumbs up and share.