Space Weather Report: Solar Superstorm Could Kill Majority of In-Orbit Satellites
[Satellite News 09-15-11] A massive solar “superstorm” could endanger, and potentially kill, several weather, telecommunications, and military satellites in less than a year, according to a Space Weather research report issued earlier this month.
The report cites examples of solar storms that could deliver a crippling blow to the current in-orbit satellite infrastructure. In October 2010, scientists observed one of the largest solar storms ever recorded, which raised concerns about the safety of Earth’s satellites but did not cause any significant service outages. However, the Space Weather study states that the 2010 storm was nowhere near the size of one that was observed in 1859 and that a similar event would produce unseen consequences.
“The [October 2010] storms revealed significant erosion of the plasmasphere, but not enough to let significant radiation into the inner belt. When the plasmapause extends to larger distances, electrons accelerated by resonant wave-particle interactions in the inner radiation belt will find themselves in a very different plasma environment and strong fluxes may persist for several years after such a storm,” the report said. “Such intensification of the near-Earth plasma environment would substantially decrease satellite lifetimes at low-Earth orbit.”
The report warns satellite operators that radiation mitigation strategies for satellites operating in the inner belt should include a consideration of the potential for a dramatic increase in the near-Earth radiation. “Such intensification of the near-Earth radiation environment may be truly devastating and would substantially decrease the lifetimes of meteorological, communication, and military satellites,” the report said. “In particular, relativistic electrons are responsible for deep dielectric charging in sensitive electronic components and may cause frequent satellite failures and operational problems.”
A majority of satellites fly through the inner radiation belt surrounding the Earth (the Van Allen Belt) during some point in their orbit. Satellites are shielded from the relatively stable radiation of the Van Allen Belt thanks to high-energy particles in the plasmasphere. Most radiation produced by a solar storm either hits the outer radiation belt or the plasmaphere. When the plasmasphere gets hit, some of the plasma dissipates, making it smaller, but that dissipation prevents too much intense radiation from hitting the inner belt.
The October storm, however, showed waves of strong radiation continually moving through the inner belt. The report’s authors suggested that the high radiation intensity of the inner belt could persist for as long as a decade and that the intensity would likely swamp the radiation shielding on a typical satellite and render it inoperable within a year after the storm.
“The lifetime of a typical satellite may decrease to less than one year,” the report said. “The potential economic loss from such a storm may be devastating. Enhancements of the inner belt will mostly affect satellites in polar and low Earth orbit, which include but are not limited to weather, military, and telecommunication satellites.”
The report said that measurements made by the upcoming NASA Radiation Belt Storm Probe (RBSP) will allow scientist to more accurately determine the acceleration processes and the dynamics of the radiation belts. The results could help satellite operators develop methods to mitigate the impact of solar superstorms.
“The main goal of the current study is to simulate a perfect storm that may occur in the future and estimate the potential effect of such a storm on the near-Earth radiation environment and on the satellites traversing the inner radiation zone,” the report said. “Spacecraft engineers should include the scenario of a profound intensification of the inner zone radiation environment into their radiation mitigation strategy.”