Magnetospheric MHD Resonances and ULF Pulsations - Ultra and Extremely Low Frequency Electromagnetic Fields - page 259

geophysical factors can reach about 60 % of total spacecraft failures (e.g., Pilipenko
et al. 2006 ). Drastic deterioration of the space weather, that is fast increase in
solar and geomagnetic activity, may greatly affect the ground-based technological
systems and can endanger human life or health. At geostationary orbits the most
dangerous effect is the influence of energetic particles on spacecraft performance.
Depending on the particle energy, it can produce electrostatic charging followed by
the faulty operation of electronics. The space-borne equipment errors have occurred
during a magnetospheric storm just after a sharp enhancement of the relativistic
electrons flux in the magnetosphere. The effect of these electrons is appearance of
static negative charges, which can be irregularly distributed on the satellite surface
because of different electric properties of surface elements. The potential drop
between adjacent details of the satellite can reach tenth kilovolts that may result
in dielectric breakdown and solar battery damage. Due to that the magnetospheric
electrons with energy about 100 keV are termed “killer electrons.” One of the best
known events is a breakdown of American satellite TELSTAR during a magnetic
storm in 1997, that resulted in the paging disconnection in considerable regions of
the USA.
Sudden magnetospheric perturbations may greatly affect systems of commu-
nication and navigation including satellite navigation (GPS, GALLILEO and
GLONASS) which in turn result in unforeseen contingencies (e.g., Yasuda et al.
2011 ; Takada et al. 2012 ). Air carriage comes up against such serious problems
as a complete or particular loss of communication during the flight, delay of
flight or changing of the flight routine, increase in fuel consumption, and fall off
of gross weight. Moreover, the fluxes of high energy protons (with the energies
greater than 100 MeV) of the solar flares can trigger health hazard for pilots and air
travelers because of enhanced radiation background onboard. For example, the FAA
(Federal Aviation Administration), which is primarily responsible for the safety and
regulation of civil aviation in the USA, has reported that due to the strong solar flares
on October 29 and 30, 2003 the global American system of precise GPS-positioning
WAAS (Wide Area Augmentation System) was nonserviceable for aviation for 15
and 11 h, respectively. The intense radio bursts of clockwise-polarized waves in the
frequency range of L1 and L2, which is usually used for satellite navigation, have
been observed on December 2006. This results in the complete loss of GPS-signal
for 10 min. With the current trend in miniaturization of electronic equipment, the
impact of solar energetic particles greatly increases the risk of radiation damage
of particular elements which may result in false operation and the generation of
incorrect commands. For example, the failure probability of main memory module
due to an impact of individual solar high energy particle was estimated to be one
event per 200 h during the flight in polar region.
In the interest of air traffic, the space weather monitoring needs to include
measurements of solar particle fluxes and Roentgen radiation, ejections of coronal
plasma, and other characteristics of the solar activity provided by geostationary
satellites as well as the observations of the particle flux variations in polar region and
Earth radiation belts provided by polar satellites. Indices of solar and geomagnetic