Solar Storm Threat Analysis - Impact

Impact, 2007 James A. Marusek
objects and dissipate significant energy at a penetrated depth (referred to as Bragg peak). When the particles are
slowed down at their penetrated depth (for 148 MeV protons, the Bragg peak is at approximately 140 mm [5.5
inches]), the interaction time becomes larger and the value of the energy transfer is at its maximum. Now consider
the above graph as a living organism. Water is a basic chemical component in humans. At the Bragg peak, a large
amount of high-energy electrons are produced that cause multiple ionization events at the end of their range in a
distance that corresponds to the cross section of a deoxyribonucleic acid (DNA) molecule. This ionization produces
cluster damage at the DNA level. Energetic protons, neutrons and ions have a greater biological efficiency than Xrays
and Gamma Rays to induce genetic damage. X-rays can produce isolated single and double DNA strand breaks,
which can be repaired by the cells rather quickly and cleanly. High-energy proton and ion radiation produces
complex cluster damage to the DNA strands that are significantly less repairable. A macroscopic tumor may
originate from only one transformed cell. If a single mutated cell survives, cancer may develop.
Figure 4. Proton, ion and photon radiation penetration through water. 26
Sudden Cardiac Death (SCD, commonly referred to as cardiac arrest) is death of a cardiac origin occurring within 1
hour of preliminary symptoms. In general, this is caused by cardiac arrhythmias, electrical heart instability and
heart rhythm disturbances. A study by Stoupel et al. of 788 SCDs over a 36 month period in the Baku capital city of
Azerbaijan showed a correlation between SCDs and solar storms. 27 They found that days producing SCDs had an
average of 8,538 imp/min daily neutron activity, compared to the daily average of 8,475 imp/min. When they
looked at the days with the greatest number of SCDs (4-5), the neutron count on those days jumped even higher to
8,657 imp/min. High-energy neutrons are created from the collision of high energy protons and ions with the
Earth’s atmosphere. In general, they are primarily created by GCRs. But very energetic SPEs will also produce
high-energy neutrons. Therefore neutron activity can be viewed as function of both GCRs combined with very
high-energy solar cosmic rays. There is another aspect of this study that is also interesting. Refer to Table 6.
During quiet days, SCDs are solely influenced by Galactic Cosmic Rays (GCRs). But as weak solar storms pass
near the planet, SCD rates tend to drop. CMEs even mild ones contain strong magnetic fields that can efficiently
deflect incoming GCRs, shielding Earth from their effect. This phenomenon is known as the “Forbush decrease”.
Then as the intensity of the solar storm increases further, the quantity of the SPE high-energy particles increase, and
they become a dominant factor in sudden death morbidity rates. A small number of these SPE nuclear particles are
able to penetrate the Earth’s magnetic field and atmosphere and reach the planet’s surface. The intense ionization
that occurs when one of these particles enters the human body and thermalizes is sufficient to produce an electrical
pulse that short circuits the heart rhythm.
Table 6. Sudden Cardiac Death Compared to Geomagnetic Activity 27
Geomagnetic Activity
Category
SCD Distribution
Quiet (I°) 0.78
Unsettled (II°) 0.66
Active (III°) 0.64
Minor Geomagnetic Storm (IV°) 0.92
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