Space Radiation Cancer Risk Projections for Exploration Missions: Uncertainty Reduction and Mitigation

By National Aeronautics and Space Administration

In this paper we discuss expected lifetime excess cancer risks for astronauts returning from exploration class missions. For the first time we make a quantitative assessment of uncertainties in cancer risk projections for space radiation exposures. Late effects from the high charge and energy (HZE) ions present in the galactic cosmic rays including cancer and the poorly understood risks to the central nervous system constitute the major risks. Methods used to project risk in low Earth orbit are seen as highly uncertain for projecting risks on exploration missions because of the limited radiobiology data available for estimating HZE ion risks. Cancer risk projections are described as a product of many biological and physical factors, each of which has a differential range of uncertainty due to lack of data and knowledge. Monte-Carlo sampling from subjective error distributions represents the lack of knowledge in each factor to quantify risk projection overall uncertainty. Cancer risk analysis is applied to several exploration mission scenarios. At solar minimum, the number of days in space where career risk of less than the limiting 3% excess cancer mortality can be assured at a 95% confidence level is found to be only of the order of 100 days.Cucinotta, Francis and Badhwar, Gautam and Saganti, Premkumar and Schimmerling, Walter and Wilson, John and Peterson, Leif and Dicello, JohnJohnson Space Center; Langley Research CenterASTRONAUTS; CANCER; GALACTIC COSMIC RAYS; RISK; SPACE EXPLORATION; PLANETARY ENVIRONMENTS; RADIATION HAZARDS; CONFIDENCE LIMITS; LOW EARTH ORBITS; MONTE CARLO METHOD; RADIOBIOLOGY; RADIATION DOSAGE; MORTALITY; IONS; SPACE MISSIONS; MANNED SPACE FLIGHT...

• Format: Paperback
• Language: English
• ISBN: 1723888737
• ISBN13: 9781723888731
• Release Date: January 1
• Publisher: Independently Published
• Length: 64 Pages
• Weight: 0.38 lbs.
• Dimensions: 0.1" x 8.5" x 11.0"