Space Science Reviews

, Volume 179, Issue 1–4, pp 579–615 | Cite as

AE9, AP9 and SPM: New Models for Specifying the Trapped Energetic Particle and Space Plasma Environment

  • G. P. GinetEmail author
  • T. P. O’Brien
  • S. L. Huston
  • W. R. Johnston
  • T. B. Guild
  • R. Friedel
  • C. D. Lindstrom
  • C. J. Roth
  • P. Whelan
  • R. A. Quinn
  • D. Madden
  • S. Morley
  • Yi-Jiun Su


The radiation belts and plasma in the Earth’s magnetosphere pose hazards to satellite systems which restrict design and orbit options with a resultant impact on mission performance and cost. For decades the standard space environment specification used for spacecraft design has been provided by the NASA AE8 and AP8 trapped radiation belt models. There are well-known limitations on their performance, however, and the need for a new trapped radiation and plasma model has been recognized by the engineering community for some time. To address this challenge a new set of models, denoted AE9/AP9/SPM, for energetic electrons, energetic protons and space plasma has been developed. The new models offer significant improvements including more detailed spatial resolution and the quantification of uncertainty due to both space weather and instrument errors. Fundamental to the model design, construction and operation are a number of new data sets and a novel statistical approach which captures first order temporal and spatial correlations allowing for the Monte-Carlo estimation of flux thresholds for user-specified percentile levels (e.g., 50th and 95th) over the course of the mission. An overview of the model architecture, data reduction methods, statistics algorithms, user application and initial validation is presented in this paper.


Radiation belt modeling Energetic trapped particles Space environment climatology Space weather 



Many people have been involved in building AE9/AP9/SPM. Much credit is due Clark Groves for getting the project started. The authors especially wish to thank Joe Mazur, Bern Blake, Jim Roeder and Joe Fennell for technical advice on the HEO, ICO and POLAR/CAMMICE data; Richard Selesnick for cleaning and analysis of the SAMPEX/PET and POLAR/HISTp data and for his physics-based proton belt climatology model; Jon Niehof and Jack Scudder for access to their versions of the POLAR/MICS and POLAR/HYDRA data; Jean-Andre Sauvaud for use of the DEMETER data; Don Brautigam, Sebastien Bourdarie, Daniel Boscher, Jay Albert, Kara Perry, Brian Wie and Seth Claudepierre for technical assistance; Bill Olson, Dave Byers, James Metcalf, Michael Starks, Tim Alsruhe and Geoff Reeves for project management; Bob Weigel and Mike Xapsos for ViRBO and LWS-SET website support; Sharon Benedict for graphics support; Dave Chenette and Michael Bodeau for helping define the requirements; and the “short list” of engineers and scientists who tested the beta versions and provided valuable feedback all along the way. This work was supported through Air Force contracts FA8718-05-C-0036, FA8718-10-C-001, FA8721-05-C-0002 and FA8802-09-C-0001 and NASA grant NNG05GM22G.


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Copyright information

© US Government 2013

Authors and Affiliations

  • G. P. Ginet
    • 1
    Email author
  • T. P. O’Brien
    • 2
  • S. L. Huston
    • 3
  • W. R. Johnston
    • 4
  • T. B. Guild
    • 2
  • R. Friedel
    • 6
  • C. D. Lindstrom
    • 4
  • C. J. Roth
    • 5
  • P. Whelan
    • 5
  • R. A. Quinn
    • 5
  • D. Madden
    • 3
  • S. Morley
    • 6
  • Yi-Jiun Su
    • 4
  1. 1.MIT Lincoln LaboratoryLexingtonUSA
  2. 2.The Aerospace CorporationChantillyUSA
  3. 3.The Institute for Scientific Research, 400 St. Clement’s HallBoston CollegeChestnut HillUSA
  4. 4.Space Vehicles DirectorateAir Force Research LaboratoryKirtland AFBUSA
  5. 5.Atmospheric and Environmental Research, IncorporatedLexingtonUSA
  6. 6.Los Alamos National LaboratoryLos AlamosUSA

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