Solar Storm Threat Analysis - Impact

Impact, 2007 James A. Marusek
Some of the memory damage is soft causing Single Event Upset (SEU). Generally, this anomaly can be corrected
by a computer reboot. But some of the damage can be hard causing unrepairable physical damage to the junction of
the microcircuit. These types of failures can be fatal. 3
Satellites receive their operating power from large solar panels arrays. High-energy protons from SPEs and CMEs
can damage the solar cells by causing the silicon atoms in the solar cell matrix substrate to violently shift position
which produce crystal defects. These defects increase the resistance of the solar cells to electrical current. As a
direct result, solar cell efficiency steadily decreases and solar panel power drops off. 3 A single strong solar storm
can decrease lifetime of a satellite’s solar panels by several years.
One critical satellite system that is very sensitive to damage from solar storms is the Attitude Control System. If the
system is damaged or compromised, the satellite will become disoriented. Without accurate orientation data, the
satellite will be unable to make fine adjustments to its orbit to prevent the satellite from reentering Earth’s
atmosphere and burning up.
Another threat is differential charging. Charged particles striking different areas of a spacecraft can cause these
sections of the spacecraft to be charged to different levels. Spacecraft may experience extensive surface charging as
static electrical fields as high as 1,000 volts build up on the skin of the spacecraft. Electrical discharges can arc
across the spacecraft components harming and potentially disabling them.
The satellite damage triggered from high-energy nuclear particles in solar storms produce a morass of delayed
effects and complex phenomena that can lead to the loss of the satellite weeks or months later. 3 In one study,
approximately 6,000 satellite malfunctions onboard Soviet “Kosmos” satellites over the period of 1971-1999 were
analyzed to better understand the effects of solar storms. The analysis revealed there was a lag time between
commencement of the geomagnetic storm [arrival of the CME] and the peak period of satellite malfunctions. For
low-altitude (< 1,000 km) orbit satellites, the peak occurs approximately 5 days after the beginning of the storm.
For high altitude (> 1,000 km) orbit satellites, the peak occurs approximately 2 days after the beginning of the
storm. 29 This lag time is associated with the accumulating nature of the damage effects. The full extent of the
damage from a massive solar storm may not be completely apparent until several weeks later.
C. Air and Ground Based Electronics
High-energy nuclear particles in a solar storm can affect aircraft avionics, passengers with cardiac pacemakers, and
they can cause aircraft onboard computers to crash. A new class of high-altitude hybrid airships/dirigibles is being
developed as extended loitering time, sensor/communication platforms. The higher the altitude the greater the
vulnerability to the effects of electronics damage from nuclear particle radiation from SPEs.
A few high-energy nuclear particles and ions (energy levels greater than 500 MeV) within an SPE can travel all the
way down to the planet’s surface. This can produce equipment damage similar to the damage observed on
spacecraft. The area most vulnerable are the regions of magnetic pole reversals, such as the South Atlantic Anomaly.
V. Ionospheric Reflectivity and Scintillation
Solar storms can affect radio communications, satellite communications, radars and navigation systems. On
frequencies below 30 MHz, the ionosphere generally acts as an efficient reflector, allowing radio communications to
distances of many thousands of miles. Radio signals on frequencies above 30 MHz usually penetrate the ionosphere
Figure 5. The electromagnetic spectrum including x-rays, visible light, and radio waves. 30
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