Plasma Magnetic Shield for Radiation Shielding and Crew Protection

摘要

Exposure to the energetic particles associated with solar energetic particle eventsrn(SEP's) and galactic cosmic rays (GCR's) are known radiation hazards for human exploration.rnMaterial shielding and superconducting solutions add substantial mass to spacecraft and providernshielding over very limited areas. This paper will present the shielding capabilities of PlasmarnMagnetic Shield (PMS) which makes use of ambient low density plasma ejected from thernspacecraft that supports the large scale currents required to provide sufficient magnetic flux torndeflect SEPs and GCRs at large distances. The plasma currents are produced and sustained by arnRotating Magnetic Field (RMF) produced by a pair of polyphase antennas. The antennas consistrnof simple hoops on the order of 100 m scale or more, and are driven by a tuned oscillator circuitrndriven by solid state devices at kHz frequencies. The associated magnetic field from the drivenrnplasma currents make up what is referred to as a plasma magnet. The size of the plasma magnetrncan be made such that it offers protection of the spacecraft but also protection of astronautsrninvolved in EVAs and/or lunar surface exploration. Since the energetic particles do not interactrnwith any nuclei, issues of exposure to hazardous secondaries are also minimized. The proposedrnsystem has been produced experimentally on a smaller scale and modeled numerically with all thernresults strongly indicating that the proposed active shielding can indeed be achieved. Thernchallenge will be in determining accurate scaling laws to large scale within the confines of arnsmall terrestrial vacuum chamber. Results to date, and the expected operating parameters of thernPMS will be presented. Future work would seek to quantify the power and mass requirements ofrnan optimized system from a large chamber experiment with extrapolation from validated computerrnsimulations to true space conditions.