Galactic Cosmic Rays (GCR's) are considered a threat to aviators, flight crews and frequent air travelers. This risk to astronauts is even greater (possibly even lethal) and continues to pose a significant obstacle to long expeditions into outer space.
Cosmic radiation is comprised of high-energy subatomic particles from all of the natural elements in the periodic table. According to NASA, "about 90% of the cosmic ray nuclei are hydrogen (protons), about 9% are helium (alpha particles), and all of the rest of the elements make up only 1%".
Radiation exposure comparison to medical imaging studies:
- Chest X-Ray: 0.1 mSv
- Body CT Scan: 10.0 mSv
- Chest CT Scan: 8.0 mSv
- Mammogram: 0.7 mSv
Variables Affecting Cosmic Radiation Exposure
- Latitude: GCR at the poles is increased 2.5 to 5 times compared to the equator
- Altitude: The density of the atmosphere diminishes with increasing elevation
- Sun Cycle: The sun's magnetic field reverses every 11 years
- Duration: Longer exposure means larger overall dose
Health Effects of Cosmic Radiation
- Increased risk of cancer
- Increased risk for genetic defects to a developing fetus
- Increased risk for genetic defects to future offspring
- Degeneration of tissues - Cataracts
Need an FAA Medical Exam?