The Hazards of Spaceflight

As humankind presses outward toward the stars, we face a veritable host of hazards that threaten both our bodies and our minds. An array of factors must be considered when planning a lengthy space mission in order to keep astronauts safe and healthy.

Perhaps the most immediate requirement for a human being in space would be an acceptably composed and pressurized atmosphere, and on a spacefaring vessel this must be accomplished artificially. While this multivariate equation can indeed vary to some extent, what matters most is the atmosphere’s partial oxygen pressure in relation to the other gasses present. Partial oxygen pressure at sea-level on Earth is 22,700 pascals, and while human beings are able to tolerate fairly significant increases and dips in this pressure, at less than 13,400 pascals or over 32,000 pascals, the lungs are not capable of properly functioning. Furthermore, pure oxygen presents dangers of its own, including fire risk and oxygen toxicity; and maintaining an acceptable partial carbon dioxide pressure is also important for any vessels which may be using plants in their life support systems—therefore we must strike a deceptively delicate balance.

Weightlessness can cause some fairly strange and undesirable effects on the human body, which stresses the importance of the normal gravity provided by Earth. Without gravity, bones will not produce enough calcium to protect them against fracture, spines will become extended, and faces will fill with fluid, among a variety of other physiological changes—some of which would be irreversible. Furthermore, aerosolized food particulates floating around can be extremely unsanitary, further exacerbating matters. In order to help counteract these effects, a seriously strict exercise regiment must be implemented for astronauts, and rotating the space structure in order to simulate gravity would further help to provide better conditions.

Radiation presents another substantial issue for spaceborne humans; but solar flares and cosmic rays are not the only types of radiation that must be prepared for—radiation from power supplies and engines must be considered, as well. The detrimental effects of overexposure to ionizing radiation on a human body can be utterly ghastly, including genetic damage and various types of cancer (on the more merciful end of the spectrum). For this reason, some form of shielding will be needed at all times, with special additional shielding available to be deployed in the event of a solar flare.

Finally, the psychological effects of extended isolated confinement cannot be understated. Weightlessness can upset one’s equilibrium, which can alter one’s ability to perceive things normally, which can cause psychological problems. Lack of mental stimulation can cause diminished brain activity, which can trigger apathy; and while pre-mission testing will typically weed out individuals with claustrophobic tendencies, severe experiences can induce this extreme anxiety. Loss of identity and solipsism syndrome—a condition wherein an observer believes their perceptions are all that exist—can occur with the absence of stimuli. Missions must be designed to provide maximum mental stimulation, including in-flight activities, as well as supportive psychotherapy to help combat these adverse effects.