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MoonFaker: Radiation Reloaded.

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Published on Dec 18, 2016

This video would have been released over a year and a half ago if not for the fact that I have become a modern day slave to my astrophysics and geology courses. Constantly bombarded with lectures, weekly quizzes, assignments, and exams. Even the mid-semester breaks and winter breaks have been occupied by geology excursions. I just don't have as much time for producing videos as I used to. I had hoped to release this video on December 10th to coincide with the 8th anniversary of Ralph René's passing, but I had technical problems all week.

About a year ago, I released a video calculating the dose rates from 10-100MeV electrons in the Van Allen belt. A few months later, Robert Braeunig responded by posting a review on his site. He also posted a separate article titled "Apollo and the Van Allen Belts: an estimate of the radiation dose received".

In that article, he cites fluxes from the AE-8 and AP-8 models (collectively referred to as AX-8) for the Van Allen fluxes, does some calculations and concludes that the Apollo astronauts would survive the trajectory through the belts. However, a critical analysis of Braeunig's article reveals it be based on outdated data and many flawed assumptions.

Specially: Concluding from outdated 1937-1947 sources that 8g/cm^2 that will attenuate all protons with energies up to 100MeV, when in fact it would only attenuate protons with energies up to 8MeV [J.W. Keller et al. 1963]; Using a fallacy of equivalence to insist that any particles penetrating through the CSM will also pass clean through the astronauts' bodies, depositing little energy and thus causing little damage. Despite the fact that medics specializing in Proton Therapy accelerate protons to the several hundreds of MeV - within the same energy range as Van Allen protons - specifically so they will not penetrate further than the tumor within the patient's tissue; And neglecting to tell his readers that protons have a range of Radiation Weight (Q) factors that one must used to convert to the equivalent dose. Instead focusing on a Q-factor of 2, as though it is an established constant. When, in fact, for solar protons - like those trapped in the Van Allen belts - a Q-factor of 5 is more appropriate. For example, Q ≈ 5 is consistent with E.E. Kovalev's dose estimates for 30MeV proton events.

But Braeunig's article highlights a logical flaw exhibited not only by him and other propagandists, but even some professionals. While the AX-8 models for the Van Allen fluxes were considered the industry standard for quite some time, astrophysicists who seriously research the Van Allen belts know better than to take the AX-8 as gospel. Because they know it is heavily compromised.

The AP-8 only goes up to 400MeV and the AE-8 stops at 7MeV. Towards these peak energies, the fluxes diminish to insignificant numbers. Propagandists interpret this as meaning that there are almost no high-energy protons and electrons in the belts. But in fact, when compared to actual observations, the AP-8 predictions frequently underestimate the proton flux. In the case of a ~30° inclination orbit, by a factor of 3. And substantial fluxes of greater than 15MeV electrons are typically observed in both belts around 1.5 Earth radii and between 4-5 Earth radii [H.O. Funsten et al. 2013].

The reason why the AX8 underestimates these fluxes is because the higher the energy of the particles, the harder they are to measure. In the case of 15MeV electrons, for example, they pass right through the detector depositing little energy and will always create secondary bremmstrahlung x-ray photons that will also be detected as noise in the read outs. Measuring them also requires large and heavy detectors, which typically are not flown [G.D. Reeves, personal communication].

In other words, the AP-8 and AE-8 models are useless for determining the dangers one would encounter on a trip through the belts unless you apply the appropriate correction factors and Q-factors. Upon doing such, we find the fluxes of 8-400MeV protons in the Van Allen belt on the two-way trip attributed to Apollo 11 would result in a dose between ~40-100rad. With the estimates for secondary neutrons also considered, the dose is ~52-130rad.

Viewers wishing to verify my calculations are offered this link containing pdfs of my tables and a link to the AE-8/AP-8 website. Simply copy and paste the L and B/B0 coordinates listed in my tables into the AP-8 Max search engine for integral flux. This will give you the raw uncorrected proton flux, which you can then use to repeat the steps explained in this video and the pdfs to obtain the resulting doses.

http://moonfaker.com/documents/AP8-ca...
http://ccmc.gsfc.nasa.gov/modelweb/mo...

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