Solar Storm Threat Analysis - Impact
Solar Storm Threat Analysis - Impact
Solar Storm Threat Analysis - Impact
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<strong>Impact</strong>, 2007 James A. Marusek<br />
Some of the memory damage is soft causing Single Event Upset (SEU). Generally, this anomaly can be corrected<br />
by a computer reboot. But some of the damage can be hard causing unrepairable physical damage to the junction of<br />
the microcircuit. These types of failures can be fatal. 3<br />
Satellites receive their operating power from large solar panels arrays. High-energy protons from SPEs and CMEs<br />
can damage the solar cells by causing the silicon atoms in the solar cell matrix substrate to violently shift position<br />
which produce crystal defects. These defects increase the resistance of the solar cells to electrical current. As a<br />
direct result, solar cell efficiency steadily decreases and solar panel power drops off. 3 A single strong solar storm<br />
can decrease lifetime of a satellite’s solar panels by several years.<br />
One critical satellite system that is very sensitive to damage from solar storms is the Attitude Control System. If the<br />
system is damaged or compromised, the satellite will become disoriented. Without accurate orientation data, the<br />
satellite will be unable to make fine adjustments to its orbit to prevent the satellite from reentering Earth’s<br />
atmosphere and burning up.<br />
Another threat is differential charging. Charged particles striking different areas of a spacecraft can cause these<br />
sections of the spacecraft to be charged to different levels. Spacecraft may experience extensive surface charging as<br />
static electrical fields as high as 1,000 volts build up on the skin of the spacecraft. Electrical discharges can arc<br />
across the spacecraft components harming and potentially disabling them.<br />
The satellite damage triggered from high-energy nuclear particles in solar storms produce a morass of delayed<br />
effects and complex phenomena that can lead to the loss of the satellite weeks or months later. 3 In one study,<br />
approximately 6,000 satellite malfunctions onboard Soviet “Kosmos” satellites over the period of 1971-1999 were<br />
analyzed to better understand the effects of solar storms. The analysis revealed there was a lag time between<br />
commencement of the geomagnetic storm [arrival of the CME] and the peak period of satellite malfunctions. For<br />
low-altitude (< 1,000 km) orbit satellites, the peak occurs approximately 5 days after the beginning of the storm.<br />
For high altitude (> 1,000 km) orbit satellites, the peak occurs approximately 2 days after the beginning of the<br />
storm. 29 This lag time is associated with the accumulating nature of the damage effects. The full extent of the<br />
damage from a massive solar storm may not be completely apparent until several weeks later.<br />
C. Air and Ground Based Electronics<br />
High-energy nuclear particles in a solar storm can affect aircraft avionics, passengers with cardiac pacemakers, and<br />
they can cause aircraft onboard computers to crash. A new class of high-altitude hybrid airships/dirigibles is being<br />
developed as extended loitering time, sensor/communication platforms. The higher the altitude the greater the<br />
vulnerability to the effects of electronics damage from nuclear particle radiation from SPEs.<br />
A few high-energy nuclear particles and ions (energy levels greater than 500 MeV) within an SPE can travel all the<br />
way down to the planet’s surface. This can produce equipment damage similar to the damage observed on<br />
spacecraft. The area most vulnerable are the regions of magnetic pole reversals, such as the South Atlantic Anomaly.<br />
V. Ionospheric Reflectivity and Scintillation<br />
<strong>Solar</strong> storms can affect radio communications, satellite communications, radars and navigation systems. On<br />
frequencies below 30 MHz, the ionosphere generally acts as an efficient reflector, allowing radio communications to<br />
distances of many thousands of miles. Radio signals on frequencies above 30 MHz usually penetrate the ionosphere<br />
Figure 5. The electromagnetic spectrum including x-rays, visible light, and radio waves. 30<br />
21