Quantum11":1hiyt5a8 said:
If you would care to discuss what materials in the Apollo suits protected from micrometeorites. And then perhaps you can further that by describing what radiation protection the suits offered as well?
Sure.
As an additional offering to further explain the considerations surrounding radiation and high velocity particles ("cosmic rays", etc..)
RADIATION PROTECTION AND INSTRUMENTATION (Includes Van Allen Belt data)
THE BIOLOGICAL EFFECTS OF HZE GALACTIC COSMIC RADIATION (Includes data on assessments regarding high velocity particles and biological risks from actual studies conducted on Apollo missions)
MICROBIAL RESPONSE TO SPACE ENVIRONMENT EXPERIMENT (Experiments and their conclusions concerning further considerations regarding radiation on biology.)
APOLLO 17 POCKET MOUSE EXPERIMENT (Mice, bravely sacrificing themselves so we can go to the Moon.)
Read the conclusions.
If you'd like to learn how the suits worked, here's the manual -
Apollo Operations Handbook Extravehicular Mobility Unit
Detailed report on the development of the Apollo EMU.
AER-Development...EMU.pdf
Average radiation doses received for flight crews of all Apollo flights -
Solar energetic phenomena and radiation hazards to biological systems
Now that you're intimately familiar with the effects of spaceborn radiation on biological systesm, both the expected (due to experimental evidence) and actual radiation doses received by Apollo flight crews and the variety of components within the Lunar EMUs, we come to:
Apollo Experience Report - Protection Against Radiation
So, in short, what protection did they have? As far as the EMU goes, the materials of construction would protect them against low energy particles and radiation. Neutrons generated from secondary radiation (particles impacting the lunar surface) were also mitigated, somewhat, by the materials of construction including neutron-resonant foils. However, Radiation was never a significant problem with any of the Apollo missions and it was not thought to be one unless a solar flare occurred. In that case, it was hoped the astronauts would make it back to the LEM before significant damage by high v cosmic radiation could take place. Though, at the time, little was known concerning cosmic rays. Later, it was determined that inside the flight capsule, crews could survive radiation from a solar flare. However, secondary radiation might be a problem and further effort for protection was made. Cosmic rays, as it turns out, generally need repeated strikes to do significant damage to the most concerning organ - the brain. Incidental damage from occassional strikes was not thought to be of significance. (Remember the "Eye Flashes?" The summary from those incidents is also included in the links above.)
As it stands, Apollo flight crews did not return home with any dosages higher than what were already recommended as yearly limits set by the USAEC. (Atomic Energy Commission -The authority at that time.)
The only specifically constructed anti-radiation (aside from heavy thermal insulation, materials of general constuction/dual purpose and some neutron protection) component on the Apollo EMU that I know of was the gold visor used to protect against UV and infra-red radiation. Oh, and all EMUs came with a handy dosimeter, in an external pocket...
That should answer your question.