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Light Flashes Observed by Astronauts on Apollo 11 through Apollo 17
Science (New York, N.Y.)
|March 8, 1974
Summary
Apollo astronauts saw cosmic ray flashes in their eyes. Analysis revealed fewer flashes occurred during the return journey compared to the trip to the Moon.
Area of Science:
- Space science
- Particle physics
- Human physiology
Background:
- Astronauts on Apollo missions reported observing unexplained light flashes.
- These phenomena were hypothesized to be caused by high-energy cosmic ray nuclei.
- Understanding these events is crucial for astronaut safety during deep space missions.
Purpose of the Study:
- To analyze the frequency and characteristics of light flash observations during Apollo missions.
- To investigate the potential correlation between cosmic ray flux and observed light flashes.
- To compare event rates during translunar and transearth coast phases.
Main Methods:
- Reviewing astronaut debriefing reports and scientific logs from the last seven Apollo missions.
- Analyzing recorded data on the frequency of light flash observations.
- Comparing event rates between different mission phases (translunar vs. transearth coast).
Main Results:
- Confirmed consistent observation of light flashes across multiple missions.
- Tentatively attributed flashes to cosmic ray nuclei (atomic number >= 6) traversing astronaut's eyes.
- Observed a significantly lower rate of flashes during transearth coast compared to translunar coast.
Conclusions:
- Cosmic ray nuclei are a likely source of the observed light flashes.
- The difference in event rates suggests variations in cosmic ray flux or shielding during different mission phases.
- Further research is needed to fully understand cosmic ray interactions with the human visual system in space.
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