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24 May 2012

Answer to Question #791 Submitted to "Ask the Experts"

Category: Environmental and Background Radiation — Space Flight

The following question was answered by an expert in the appropriate field:

What type of radiaton do astronauts receive and how much of it do they get while in space?

Astronauts receive radiation exposures in space that depend strongly on the type of mission (low-Earth orbit, deep space, etc.), mission duration (days, weeks, months, or years), and the phase of the approximate 11-year solar cycle.

Radiation exposure sources include the Van Allen belts (protons and electrons trapped by the Earth's magnetic field), galactic cosmic rays (nuclei of all known natural elements, which permeate all of space to some degree), and energetic solar particles (mainly protons, alpha particles, and some heavier ions).

An excellent source of information on astronaut radiation exposures and measures used to protect them is available at NASA Johnson Space Center. Other excellent sources of information are the November 2000 issue of Health Physics, which contains the proceedings of the 1998 Annual Meeting of the National Council on Radiation Protection and Measurements, and NCRP.

Larry Townsend, PhD

Answer posted on 12 April 2001. The information and material posted on this website is intended as general reference information only. Specific facts and circumstances may alter the concepts and applications of materials and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice specific to whatever facts and circumstances are presented in any given situation. Answers are correct at the time they are posted on the Website. Be advised that over time, some requirements could change, new data could be made available, or Internet links could change. For answers that have been posted for several months or longer, please check the current status of the posted information prior to using the responses for specific applications.