Speaker
Dr
Daniel Heynderickx
(DH Consultancy BVBA)
Description
Activity: INFRA
Contractor(s): DHC (B) & Kallisto (UK)
Technical Officer: Hugh Evans
Summary:
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. 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.
These newly developed AE-9/AP-9 models are gradually being used by satellite companies for radiation analyses. Several model users from ESA member states have signalled significant differences in simulations performed with the new generation of models compared to AE-8/AP-8 results, prompting concern with industry, as radiation protection levels would be required to change significantly, potentially impacting on radiation design margins.
A preliminary validation of the AE-9/AP-9 models has been performed, comparing the results of these new models against radiation environment datasets (CRRES/MEA, AZUR/EI-88, GioveB/SREM, INTEGRAL/IREM and SAMPEX/PET) as well as results from other radiation environment models for common orbits (SSO, GEO, GNSS, SSO).
