James Van Allen Radiation Belts discovered in 1958

Radiation Primer here

A radiation belt is a layer of energetic charged particles that is held in place around a magnetized planet, such as the Earth, by the planet’s magnetic field. The Earth has two such belts and sometimes others may be temporarily created. The discovery of the belts is credited to James Van Allen and as a result the Earth’s belts bear his name.

The main belts extend from an altitude of about 1,000 to 60,000 kilometers above the surface in which region radiation levels vary. Most of the particles that form the belts are thought to come from solar wind and other particles by cosmic rays.^[1] The belts are located in the inner region of the Earth’s magnetosphere. The belts contain energetic electrons that form the outer belt and a combination of protons and electrons that form the inner belt.

The radiation belts additionally contain lesser amounts of other nuclei, such as alpha particles. The belts endanger satellites, which must protect their sensitive components with adequate shielding if their orbit spends significant time in the radiation belts. In 2013, NASA reported that the Van Allen Probes had discovered a transient, third radiation belt, which was observed for four weeks until destroyed by a powerful, interplanetary shock wave from the Sun.

The Apollo missions marked the first event where humans traveled through the Van Allen belts, which was one of several radiation hazards known by mission planners.

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NASA scientist admits they can’t get past the Van Allen Belts

 

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Scientific American March 1959 pdf

Our measurements show that the maximum radiation level as of 1958 is equivalent to between 10 and 100 roentgens per hour, depending on the still-undetermined proportion of protons to electrons.  Since a human being exposed for two days to even 10 roentgens would have only an even chance of survival, the radiation belts obviously present an obstacle to space flight.

 Unless some practical way can be found to shield space-travelers against the effects of the radiation, manned space rockets can best take off through the radiation-free zone over the poles.  A “space station” must orbit below 400 miles or beyond 30,000 miles from the earth.  We are now planning a satellite flight that will test the efficacy of various methods of shielding.

The hazard to space-travelers may not end even when they have passed the terrestrial radiation belts.  According to present knowledge the other planets of our solar system may have magnetic fields comparable to the earth’s and thus may possess radiation belts of their own.  The moon, however, probably has no belt, because its magnetic field appears to be feeble.  Lunar probes should give us more definite information on this point before long.

 

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WTF? #1

Once you are past the Van Allen shields, for example between the earth and the moon, you would be subject to the full brunt of solar flares. The Van Allen shields protect us here on Earth from this deadly radiation.

For occupational exposure dose limits, the International Atomic Energy Agency states that the “occupational exposure of any worker shall be so controlled” that the limit of an “effective dose of 50 mSv” “in any single year” “be not exceeded”. 50 mSv converts to 5 rems.

How were the Apollo astronauts able to withstand 375 rems per day when the IAEA occupational exposure dose limit is only 5 rems in any single year?

How did the astronauts survive the deadly radiation without the protection of the Van Allen belts while on the moon?

The hulls of the Apollo spacecraft were ultra-thin. They would have been unable to stop any significant amount of radiation. The same can be said for the spacesuits.

From National Library of Medicine:

Interplanetary crew exposure estimates for the August 1972 and October 1989 solar particle events.

“A comparison of risk assessment in terms of total absorbed dose for each event is made for the skin, ocular lens, and bone marrow. Overall, the doses associated with the August 1972 event were higher than those with the October 1989 event and appear to be more limiting when compared with current guidelines for dose limits for missions in low Earth orbit and more hazardous with regard to potential acute effects on these organs.”

“Both events could be life-threatening if adequate shielding is not provided.”

“The area between the Sun and the planets has been termed the interplanetary medium. Although sometimes considered a perfect vacuum, this is actually a turbulent area dominated by the solar wind, which flows at velocities of approximately 250-1000 km/s (about 600,000 to 2,000,000 miles per hour).

Other characteristics of the solar wind (density, composition, and magnetic field strength, among others) vary with changing conditions on the Sun. The effect of the solar wind can be seen in the tails of comets (which always point away from the Sun).”

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How could astronots you withstand hours of X-rays?

Dentists only use X-rays for about a second.

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WTF? # 2

Astronaut Alan Bean Doesn’t Know If The Went Through VA Belts

“I am not sure we went far enough out to encounter the Van Allen radiation belts. Maybe we did.”

When Sibrel pointed out the Belts were 1000 miles out, Bean tossed up his hands and replied, “Then we went right out through them.”

“No effects on yourselves?” asked Sibrel.

Bean shook his head. “Uh-uh, didn’t even know it. I don’t think anyone even, well, maybe someone said ‘you went through the radiation belt’ (fidgets, takes his right hand and begins scratching his right temple, closes his eyes) and but we didn’t feel it inside. And we didn’t get any added radiation.”

How did Bean know they didn’t get any added radiation when he didn’t even know the Belts existed twenty seconds earlier?

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California Academy of Sciences says the Van Allen Belts are deadly in 1959. Why would they not be deadly in 1969?

“The Earth is surrounded by intense radiation.”
Dr. Earl S. Harold  on his Science In Action series.
California Academy of Sciences

Van Allen didn’t win his many awards for discovering a belt of harmless radiation.
“The radiation was so strong it stopped his Geiger counters
in Explorer 1, 2 (blew up) and 3″

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How Astronauts Got Through the Van Allen Belt. The Scientists Story.

The Van Allen belts span only about forty degrees of earth’s latitude — twenty degrees above and below the magnetic equator. The diagrams of Apollo’s translunar trajectory printed in various press releases are not entirely accurate. They tend to show only a two-dimensional version of the actual trajectory. The actual trajectory was three-dimensional. The highly technical reports of Apollo, accessible to but not generally understood by the public, give the three-dimensional details of the translunar trajectory.

Each mission flew a slightly different trajectory in order to access its landing site, but the orbital inclination of the translunar coast trajectory was always in the neighborhood of 30°. Stated another way, the geometric plane containing the translunar trajectory was inclined to the earth’s equator by about 30°. A spacecraft following that trajectory would bypass all but the edges of the Van Allen belts.

This is not to dispute that passage through the Van Allen belts would be dangerous. But NASA conducted a series of experiments designed to investigate the nature of the Van Allen belts, culminating in the repeated traversal of the Southern Atlantic Magnetic Anomaly (an intense, low-hanging patch of Van Allen belt) by the Gemini 10 astronauts.

….Metals can be used to shield against particle radiation, but they are not the ideal substance. Polyethylene is the choice of particle shielding today, and various substances were available to the Apollo engineers to absorb Van Allen radiation. The fibrous insulation between the inner and outer hulls of the command module was likely the most effective form of radiation shielding. When metals must be used in spacecraft (e.g., for structural strength) then a lighter metal such as aluminum is better than heavier metals such as steel or lead.

( Polyethelene is what I store my water in. They are saying it stops deadly solar radiation…ha ha ha ha ha ..)

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The hulls of the Apollo spacecraft were ultra-thin. They would have been unable to stop any significant amount of radiation. The same can be said for the spacesuits.

WTF? # 3

Space Ships Hull Design.

As we learned from Chernobyl and now Fukushima is that 9 ft. of concrete cannot contain deadly radiation..but light shell in space, exposed with solar radiation for nearly the entire journey, can. hmm

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WTF? #4

Solar Flares

“Solar Flares are produced by ‘storms’ in the solar magnetosphere. These eruptions yield very high radiation doses within very short time periods (hours to days). There is a correlation with the 11 year solar cycle. The largest events occurring in the months following sunspot maximum. Solar flares are cataclysmic releases of energy resulting from processes that are poorly understood.”

On January 20th, 2005, a giant sunspot named “NOAA 720” exploded. The blast sparked an X-class solar flare, the most powerful kind, and hurled a billion-ton cloud of electrified gas (a “coronal mass ejection”) into space. Solar protons accelerated to nearly light speed by the explosion reached the Earth-Moon system minutes after the flare–the beginning of a days-long “proton storm.”

Here on Earth, no one suffered. Our planet’s thick atmosphere and magnetic field protects us from protons and other forms of solar radiation. In fact, the storm was good. When the plodding coronal mass ejection arrived 36 hours later and hit Earth’s magnetic field, sky watchers in Europe saw the brightest and prettiest auroras in years: gallery.

The Moon is a different story.

“The Moon is totally exposed to solar flares,” explains solar physicist David Hathaway of the Marshall Space Flight Center. “It has no atmosphere or magnetic field to deflect radiation.” Protons rushing at the Moon simply hit the ground–or whoever might be walking around outside.

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The Van Allen radiation belt simply cannot be penetrated safely
without massive lead shield

Lead Shielding Required to get through Van Allen Belts

Dr. E. E. Kovalev
Radiation Protection During Space Flight
Institute of Biomedical Problems, USSR Ministry of Health
Moscow 123007, USSR

 

Did They Try to Blow A Nuke a Hole Through the VA Belt? Project Starfish (1962)

On July 9, 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 kilometers 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 under-standing 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). “On 19 July… NASA announced that as a consequence of the high altitude nuclear test of July 9, a new radiation belt had been formed, stretching from a height of about 400 km to 1600 km; it can be seen as a temporary extension of the lower Van Allen Belt” (K.H.A. 5 August 1962).