Reducing space radiation cancer risk with magnetic shielding

Abstract Interplanetary space radiation presents significant hazards to astronaut health and survival because it can cause both acute and chronic health effects including carcinogenesis. Mitigation of space radiation risks remains critical for enabling human missions beyond Earth orbit. Currently available options for space radiation shielding, such as water shielding, may not be sufficient at reducing space radiation dose and cancer risk to within current regulatory limits. Active magnetic shielding using superconductors has consistently been identified for further study due to its high potential benefit. In response, we have developed Monte Carlo models to determine the effectiveness of several of the latest magnetic shielding concepts, along with current passive shielding techniques, in terms of risk of exposure induced death. This was done for various Mars flyby mission profiles according to current space agency risk tolerance limits. Our study found that few shielding options were able to meet current risk tolerance limits without relying on astronauts of advanced age (>60 years). However, all of the magnetic shielding configurations provided substantial benefit in reducing space radiation cancer risk given high magnetic field strength (7 Tesla). With this information, space agencies can move towards engineering assessments of magnetic shielding technology and begin to advance the concept into a solution enabling interplanetary travel.

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