RADHARD 2018

Radiation Hardness Assurance

Space Radiation Environment at LEO, MEO and GEO

Christoph Tscherne, Peter Beck, Marcin Latocha, Michael Wind
Seibersdorf Laboratories, Austria

Abstract

Spacecraft in near-Earth orbits are exposed to a complex and harsh radiation environment that poses a great challenge to space mission design. Radiation accelerates the aging of EEE components, eventually leading to a decrease in performance or to a complete loss of functionality [1]. Radiation exposure of astronauts, as in the ISS, is a serious concern. In order to face these challenges, it is necessary to understand the nature and effects of space radiation. The space radiation environments at Low Earth Orbits (LEO), Medium Earth Orbits (MEO) and Geostationary Earth Orbits (GEO) compose of three main types of primary radiation: solar energetic particles (SEP), galactic cosmic radiation (GCR) and particles trapped in the Earth’s radiation belts [2, 3]. All three types are of different origin, vary greatly in energy and flux and underlie short-term and long-term variations modulated by the sun’s activity [4]. The presentation introduces the different types of orbits and discusses the origin and effects of the space radiation environment at LEO, MEO and GEO in detail. Characteristics of SEP, GCR and trapped particles are described and their influence on mission design is reviewed [5].

References

[1.]  Poivey, Christian. "Total Ionizing and Non-Ionizing Dose Radiation Hardness Assurance." Short Course of NSREC 2017, 17 July 2017, New Orleans. USA. Presentation.

[2.]  Holmes-Siedle, Andrew G., and Len Adams. Handbook of radiation effects. 2nd ed., Oxford University Press, 2002.

[3.]  Santin, Giovanni. "Radiation Environments: Space, Avionics, Ground and Below." Short Course of RADECS 2017, 2 Oct. 2017, Geneva. Switzerland. Presentation.

[4.]  Viereck, Rodney. "Space Weather: What is it? How Will it Affect You?" NOAA Space Environment Center, 2007, Boulder Colorado. USA. Presentation.

[5.]  SPENVIS - The European Space Agency (ESA) Space Environment Information System (SPENVIS), Last online access at swe.ssa.esa.int; www.spenvis.oma.be in April 2018.

Acknowledgments

I acknowledge the insightful talks and presentations of the lecturers of the RADECS 2017 and NSREC 2017 short courses and the information provided by SPENVIS, ESA's Space Environment Information System (http://swe.ssa.esa.int/; www.spenvis.oma.be)