A previous post on the subject of human space travel was cautionary, and I did not leave much hope (?) to those who truly desire to visit Mars, the asteroid Ceres, or even walk in the footsteps of the intrepid Apollo astronauts. The following post is my attempt to survey the efforts of protection so that we too may gain that unique perspective.
Space travel will, one day, be routine for many on our planet; and the current period of economic hardship in which scientists and those in public outreach endure will be perceived as if it were adolescence. I believe one can see the evidence in the trends which appear cyclical. Although I have no real hard data to work with—most sociologists and economists will cite the cyclical nature of political fortunes. (In a nutshell—those with money make the rules and everyone acts in their own self-interest.)
How does one shield oneself from space radiation?
There are two forms of space radiation: solar and galactic cosmic rays. Given we know how cosmic and solar radiation interact with earth-bound substances, we are several steps ahead of by knowing to protect ourselves. Basically, our “engineers” must have a fundamental understanding of materials science (e.g. plastic, metal, glass, fiber, and people, too). The concepts of how radiation (nuclear physics) interacts with atoms, bonds and molecules (or the things of our everyday lives) is tantamount to knowing how to survive in space.
We (on Earth) put sunscreen to protect our skin (?) but there is more to the picture. Just like we know that it may take multiple sunburns to eventually contract fatal cancer; in space, the concept of amount of exposure is multiplied many times over. Exposure to intense X-ray radiation (for a mere 20 minutes) may lead to acute radiation sickness. There is no (?) sunscreen lotion to protect us from harsh solar X-rays or galactic radiation, for that matter.
What we have is a rich historical past to draw our lessons of shielding. Our past missions (manned and un-manned) have given us precedent to use the following materials:
- Plastic such as polyethylene—
- Non-reactive internal equipment—
- Hydrogen fuel
The last citation may seem odd but it (hydrogen fuel) has been a source of shielding. In fact “hydrogenous” materials (e.g. water) have been the basis for shielding. Specialized (nano-fiber) blanket and coats have been used, as well.
In the final analysis, our first spacefaring citizens will take away a memorable excursion and will be considered intrepid pioneers, in some sense of the word.
Reference for post:
Durante, M. Physical basis of radiation protection in space travel, Reviews of Modern Physics, 2011, 83, 1245-1281