Radiation environment onboard spacecraft at LEO and in deep space

0486343 - ÚJF 2018 RIV US eng C - Conference Paper (international conference)
Sihver, L. - Kodaira, S. - Ambrožová, Iva - Uchihori, Y. - Shurshakov, V.
Radiation environment onboard spacecraft at LEO and in deep space.
IEEE Aerospace Conference Proceedings. Vol. 2016. New York: IEEE, 2016, č. článku 7500765. ISBN 978-1-4673-7676-1. ISSN 1095-323X.
[IEEE Aarospace Conference. Big Sky (US), 05.03.2016-12.03.2016]
Institutional support: RVO:61389005
Keywords : low Earth orbit * LEO spacecraft * dosimetry
OECD category: Aerospace engineering

It is well known that outside the Earth's protective atmosphere and magnetosphere, the environment is very harsh and unfriendly for any living organism, due to the micro gravity, lack of oxygen and protection from high energetic ionizing cosmic radiation, as well as from powerful solar energetic particles (SEPs). The space radiation exposure leads to increased health risks, including tumor lethality, circulatory diseases and damages on the central nervous systems. In case of SEP events, exposures of spacecraft crews may be lethal. Space radiation hazards are therefore recognized as a key concern for human space flight. For long-term interplanetary missions, they constitute a limiting factor since current protection limits might be approached or even exceeded. Better risk assessment requires knowledge of the radiation quality, as well as equivalent doses in critical radiosensitive organs, and different risk coefficient for different radiation caused illnesses and diseases must be developed. The use of human phantoms, simulating an astronaut's body, provides detailed information of the depth-dose distributions, and radiation quality, inside the human body. In this paper we will therefore review the major phantom experiments performed at Low Earth Orbits (LEO) [1]. However, the radiation environment in deep space is different from LEO. Based on fundamental physics principles, it is clear that hydrogen rich, light and neutron deficient materials have the best shielding properties against Galactic Cosmic Rays (GCR) [2,3]. It has also been shown [4,5] that water shielding material can reduce the dose from Trapped Particles (TP), the low energetic part of GCR, and from low energetic SEP events.
Permanent Link: http://hdl.handle.net/11104/0281177