Active shielding on Spacecraft
An exploration of the effectiveness of artificial mini-magnetospheres as a potential Solar Storm shelter for long term human space missions
R.A. Bamforda,*, B. Kelletta, J. Bradforda, T.N. Toddb, M. G. Benton, Sr.c, R. Stafford-Allenb, E.P. Alvesd, L. Silvad, C. Collingwooda, I.A. Crawforde, R. Binghamf,a
- RAL Space, STFC, Rutherford Appleton Laboratory, Harwell Oxford,
Didcot, OX11 0QX, U.K.
- Centre for Fusion Energy, Culham Science
Centre, Abingdon, Oxfordshire, OX14 3DB, U.K.
- The Boeing Company,
El Segundo, CA 90009-2919, USA.
- GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto
Superior Técnico, 1049-001 Lisboa Portugal.
- Dept of Earth and Planetary Sciences, Birkbeck College,
- University of Strathclyde, Glasgow, Scotland, UK.
In this paper we explore the effectiveness of an artificial mini-magnetosphere as a potential radiation shelter for long term human space missions. Our study includes the differences that the plasma environment makes to the efficiency of the shielding from the high energy charged particle component of solar and cosmic rays, which radically alters the power requirements. The incoming electrostatic charges are shielded by fields supported by the self captured environmental plasma of the solar wind, potentially augmented with additional density. The artificial magnetic field generated on board acts as the means of confinement and control. Evidence for similar behaviour of electromagnetic fields and ionised particles in interplanetary space can be gained by the example of the enhanced shielding effectiveness of naturally occurring "mini-magnetospheres" on the moon. The shielding effect of surface magnetic fields of the order of ~100s nanoTesla is sufficient to provide effective shielding from solar proton bombardment that culminate in visible discolouration of the lunar regolith known as "lunar swirls". Supporting evidence comes from theory, laboratory experiments and computer simulations that have been obtained on this topic. The result of this work is, hopefully, to provide the tools for a more realistic estimation of the resources versus effectiveness and risk that spacecraft engineers need to work with in designing radiation protection for long-duration human space missions.