AE9/AP9/SPM: Radiation Belt and Space Plasma Specification Models Air Force Research Laboratory (AFRL)

AE9/AP9/SPM is a new set of models for the fluxes of radiation belt and plasma particles in near-Earth space for use in space system design, mission planning, and other applications of climatological specification. Denoted AE9, AP9, and SPM for energetic Electrons, energetic Protons, and Standard Plasma Model, respectively, the models are derived from 45 data sets measured by satellite on-board sensors. These data sets have been processed to create maps of the particle fluxes along with estimates of uncertainties from both imperfect measurements and space weather variability. These estimates can be obtained as statistical confidence intervals, e.g. the median and 95th percentile, for fluxes and derived quantities, supporting design trades.

The current version of the model, V1.50.001, has been approved for public release.

  • For instructions on downloading the model, see Downloads.
  • For news on updates, bug fixes, etc., see News

The AE9/AP9/SPM Team may be reached at

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Current as of 7 January 2021