Temporal analysis of the October 1989 proton flare using computerized anatomical models

Area of Science:

• Space physics
• Radiation biology
• Space exploration safety

Background:

• Solar proton events (SPEs) pose significant radiation risks to astronauts.
• Accurate dose estimation is crucial for mission planning and crew protection.
• Previous dose estimates may overestimate exposure levels.

Purpose of the Study:

• To analyze the 1989 solar proton event using GOES-7 data.
• To estimate radiation dose rates and cumulative doses to critical organs for astronauts.
• To evaluate the effectiveness of water shielding in mitigating radiation exposure and associated risks.

Main Methods:

• Analysis of hourly averaged integral proton fluxes from GOES-7 data.
• Coupling of radiation transport calculations with detailed computerized anatomical models.
• Estimation of dose rates and cumulative doses to 20 critical body organs.
• Assessment of cancer incidence and mortality risks for varying water shield thicknesses.

Main Results:

• Estimated cumulative dose equivalents for a 5-cm water shield: 1.27 Sv (skin), 1.23 Sv (eye), 0.41 Sv (blood-forming organs).
• Results indicate 40-50% lower doses compared to 0- and 5-cm slab estimates.
• Cancer risks were quantified for astronauts under different shielding scenarios.

Conclusions:

• Water shielding is effective in reducing astronaut radiation exposure during SPEs.
• The study provides more refined dose estimates than traditional methods.
• Findings support the development of improved radiation protection strategies for space missions.