Space Tech

equatorial geomagnetic

field at Earth’s surface (14). During geomagnetic

storms, charged particles injected into the Van Allen

radiation belts from the outer magnetosphere cause a

sharp increase in the ring current, with a corresponding

decrease in Earth’s equatorial magnetic field (18). The

injected particles precipitate out of the magnetosphere

into the upper atmosphere at high latitudes, causing

auroral activity and interference w...

NASA Facts

National Aeronautics and

Space Administration

Lyndon B. Johnson Space Center

Understanding Space Radiation

FS-2002-10-080-JSC

October 2002

• Altitude above the Earth – at higher altitudes the Earth’s

magnetic field is weaker, so there is less protection against

ionizing particles, and spacecraft pass through the trapped

radiation belts more often.

• Solar cycle – the Sun has an 11-year c...