Solar storms can squish a region that was thought to provide orbital shelter
By Robert Roy Britt
Senior science writer
Updated: 5:12 p.m. ET Dec. 15, 2004
SAN FRANCISCO - A pocket of near-Earth space tucked between radiation belts gets flooded with charged particles during massive solar storms, shattering the illusion it was a safe place for satellites.
The safe zone was thought to be virtually radiation-free, a good region in which to deploy satellites so they'd be protected from the potentially debilitating effects of magnetic storms that can slam into Earth at millions of miles per hour.
But a new study of a string of severe storms last year debunks the notion. Scientists discussed the work here Wednesday at a meeting of the American Geophysical Union.
The once-suspected safe zone is called the Van Allen Radiation Belt Slot. The Van Allen belts are like two doughnuts of electrons around Earth, all trapped by the planet's magnetic field. The safe zone is a thick circular ribbon of space between the two doughnuts, from about 4,350 miles (7,000 kilometers) above the planet to 8,110 miles (13,000 kilometers) up.
NASA and the National Oceanic and Atmospheric Administration, parent of the National Weather Service, have recently pondered putting satellites into this region to avoid the radiation that affects satellites at higher and lower altitudes. (In most cases, however, satellite location is determined by imaging or communication needs.)