from Humans Are Free:
Military interest in space became intense during and after World War II because of the introduction of rocket science, the companion to nuclear technology. The early versions include the buzz bomb and guided missiles. They were thought of as potential carriers of both nuclear and conventional bombs.
Rocket technology and nuclear weapon technology developed simultaneously between 1945 and 1963. During this time of intensive atmospheric nuclear testing, explosions at various levels above and below the surface of the earth were tried.
Some of the now familiar descriptions of the earth’s protective atmosphere, such as the existence of the Van Allen belts, were based on information gained through stratospheric and ionospheric experimentation.
The earth’s atmosphere consists of the troposphere, from sea level to about 16 km above the earth’s surface; the stratosphere (which contains the ozone level) which extends from about the 16 to 48 km above the earth; and the ionosphere which extends from 48 km to over 50,000 km above the surface of the earth.
The earth’s protective atmosphere or “skin” extends beyond 3,200 km above sea level to the large magnetic fields, called the Van Allen Belts, which can capture the charged particles sprayed through the cosmos by the solar and galactic winds.
These belts were discovered in 1958 during the first weeks of the operation of America’s first satellite, Explorer I. They appear to contain charged particles trapped in the earth’s gravity and magnetic fields. Primary galactic cosmic rays enter the solar system from interstellar space, and are made up of protons with energies above 100 MeV, extending up to astronomically high energies.
They make up about 10% of the high energy rays. Solar rays are generally of lower energy, below 20 MeV (which is still high energy in earth terms). These high energy particles are affected by the earth’s magnetic field and by geomagnetic latitude (distance above or below the geomagnetic equator).
The flux density of low energy protons at the top of the atmosphere is normally greater at the poles than at the equator. The density also varies with solar activity, a minimum when solar flares are at a maximum.
The Van Allen belts capture charged particles (protons, electrons and alpha particles) and these spiral along the magnetic force lines toward the polar regions where the force lines converge. They are reflected back and forth between the magnetic force lines near the poles. The lower Van Allen Belt is about 7700 km above the earth’s surface, and the outer Van Allen Belt is about 51,500 km above the surface.
According to the Encyclopaedia Britannica, the Van Allen belts are most intense along the equator, and effectively absent over the poles. They dip to 400 km over the South Atlantic Ocean, and are about 1,000 km high over the Central Pacific Ocean.
In the lower Van Allen Belt, the proton intensity is about 20,000 particles with energy above 30 MeV per second per square centimetre. Electrons reach a maximum energy of 1 MeV, and their intensity has a maximum of 100 million per second per square centimetre. In the outer Belt, proton energy averages only 1 MeV. For comparison, most charged particles discharged in a nuclear explosion are range between 0.3 and 3 MeV, while diagnostic medical X-ray has peak voltage around 0.5 MeV.
Project Argus (1958)
Between August and September 1958, the US Navy exploded three fission type nuclear bombs 480 km above the South Atlantic Ocean, in the part of the lower Van Allen Belt closest to the earth’s surface. In addition, two hydrogen bombs were detonated 160 km over Johnston Island in the Pacific. This was called, by the military, “the biggest scientific experiment ever undertaken”.
It was designed by the US Department of Defence and the US Atomic Energy Commission, under the code name Project Argus. The purpose appears to be to assess the impact of high altitude nuclear explosions on radio transmission and radar operations because of the electro-magnetic pulse (EMP), and to increase understanding of the geomagnetic field and the behaviour of the charged particles in it.
This gigantic experiment created new (inner) magnetic radiation belts encompassing almost the whole earth, and injected sufficient electrons and other energetic particles into the ionosphere to cause world wide effects. The electrons travelled back and forth along magnetic force lines, causing an artificial “aurora” when striking the atmosphere near the North Pole. US Military planed to create a “telecommunications shield” in the ionosphere, reported in 13-20 August 1961, Keesings Historisch Archief (K.H.A.).
This shield would be created “in the ionosphere at 3,000 km height, by bringing into orbit 350,000 million copper needles, each 2-4 cm long (total weight 16 kg), forming a belt 10 km thick and 40 km wide, the needles spaced about 100 m apart.”
This was designed to replace the ionosphere “because telecommunications are impaired by magnetic storms and solar flares”. The US planned to add to the number of copper needles if the experiment proved to be successful. This plan was strongly opposed by the International Union of Astronomers.
Project Starfish (1962)
On 9 July 1962, the US began a further series of experiments with the ionosphere. From their description: “one kiloton device, at a height of 60 km and one megaton and one multi-megaton, at several hundred kilometres height” (K.H.A., 29 June 1962). These tests seriously disturbed the lower Van Allen Belt, substantially altering its shape and intensity.
“In this experiment the inner Van Allen Belt will be practically destroyed for a period of time; particles from the Belt will be transported to the atmosphere. It is anticipated that the earth’s magnetic field will be disturbed over long distances for several hours, preventing radio communication. The explosion in the inner radiation belt will create an artificial dome of polar light that will be visible from Los Angeles.”(K.H.A. 11 May 1962).
A Fijian Sailor, present at this nuclear explosion told me that the whole sky was on fire and he thought it would be the end of the world. This was the experiment which called forth the strong protest of the Queen’s Astronomer, Sir Martin Ryle in the UK.
“The ionosphere (according to the understanding at that time) that part of the atmosphere between 65 and 80 km and 280-320 km height, will be disrupted by mechanical forces caused by the pressure wave following the explosion. At the same time, large quantities of ionizing radiation will be released, further ionizing the gaseous components of the atmosphere at this height.
“This ionization effect is strengthened by the radiation from the fission products. … The lower Van Allen Belt, consisting of charged particles that move along the geomagnetic field lines … will similarly be disrupted. As a result of the explosion, this field will be locally destroyed, while countless new electrons will be introduced into the lower belt.” (K.H.A. 11 May 1962)