The Dangers of Cosmic Radiation and Possible Future Solutions

As space technology becomes more advanced and flights manned flights become longer, the perils of outer space will only become more dangerous for astronauts. As we have not yet started traveling far enough to require new fuel sources or relativistic speeds, the most prevalent health issue related to contemporary space travel is cosmic radiation.

Cosmic radiation in space is much different than on Earth. The Earth’s atmosphere deters the high energy particles that become so deadly in outer space (Durante 1247). On top of that, the wide array and randomness of particles in space makes the effects of radiation very hard to predict (Cucinotta 460). Prolonged exposure to this radiation can readily cause many varied health problems such as cancer or eye cataracts (Cucinotta 464).

The most obvious solution to the issue of radiation is to maintain a shield around the spaceship. The most likely metal candidates are lead (most likely too heavy to be used efficiently) and aluminum. The problem with these shields is that cosmic radiation causes with the nuclei in the shield to split and cause further radiation damage to the humans onboard. Figure 1 shows the probability of an aluminum shield withstanding the barrage of cosmic radiation particles over a certain period of time. Note that the mass of the shield does not seem to have much of an effect on the probability. Other nonmetal materials have yet to be extensively tested for their potential application aboard spaceships (Setlow 1014-1015).

Figure 1. Probability of complete radiation protection by an aluminum shield of variable mass over a variable length of time (from Setlow 1015)

If the structure of spacecraft cannot be properly made to stop cosmic radiation, then there may instead be hope for protecting the astronauts themselves. Research suggests that several different drugs, such as vitamin E and the steroid 5-androstenediol, may be administered to reduce tissue damage from radiation (Seed 240-243).

Before medicating astronauts becomes widely practiced, another method may be used to ensure they are safe: adapting them to the radiation. Humans living in more highly radioactive areas have consistently proven that they are less susceptible to the effects of radiation. Mortazavi and his team even assert that chronic exposure to radiation can make a potential astronaut build up an immunity or at least a resistance (Mortazavi 1544-1547). In the future, spaceships might not even defend against radiation as all astronauts (potentially a large percentage of the population) may become immune to the effects of cosmic radiation.

References

1. Durante, Marco, and Francis A. Cucinotta. “Physical basis of radiation protection in space travel.” Reviews of Modern Physics 83.4 (2011): 1245.
2. Mortazavi, SM Javad, J. R. Cameron, and A. Niroomand-Rad. “Adaptive response studies may help choose astronauts for long-term space travel.” Advances in Space Research 31.6 (2003): 1543-1551.
3. Setlow, Richard B. “The hazards of space travel.” EMBO reports 4.11 (2003): 1013-1016.
4. Seed, Thomas, et al. “New strategies for the prevention of radiation injury: possible implications for countering radiation hazards of long-term space travel.” Journal of radiation research 43.Suppl (2002): S239-S244.
5. Cucinotta, F. A., et al. “Space radiation and cataracts in astronauts.” Radiation research 156.5 (2001): 460-466.