The above display shows the median intensities of geomagnetically trapped 30 to 1100 keV electrons using the last year of observations made by a silicon solid state detector onboard the NOAA POES polar orbiting satellite. The area of very enhanced radiation centered over South America is due to the South Atlantic Magnetic Anomaly, a region where the magnetic field of the Earth is unusually weak, allowing Van Allen radiation belt particles to penetrate to an altitude that is lower than elsewhere on the globe so that the satellite can detect them. The bands of enhanced electron intensities extending across the map at higher latitudes are due to energetic electrons in the Van Allen outer radiation belt. At the highest latitudes the enhanced energetic electron fluxes are associated with auroral displays.

One-year median intensity patterns, such as this, can serve as a baseline against which particle observations made on any given day can be compared, allowing a quick determination of whether the energetic charged particle environment near the Earth was unusually low, at the median, or unusually high. This information is useful for determining the cause of anomalies in satellite systems, the degradation of radio communications (especially in the polar regions), and in supporting NASA's manned space missions.

22 Data Channels

The energetic charged particle detector that monitors the intensity of geomagnetically trapped 30-1100 keV ( >30 keV ) electrons is one of 22 energetic particle data channels, spanning a broad range of particle energies for both protons and electrons, that are available from the Space Environment Monitor (SEM-2) Medium Energy Proton and Electron Detector (MEPED) onboard NOAA POES. The 22 sensor channels span a broad range of particle energies for both protons and electrons.