Negative Effects of the Space Travel on Body

Traveling into space used to be a fictional tale. In the 1950s, children and adults all over would gather around their radios to hear stories of space men. They soon would watch images in the theaters as well as on television sets that depicted men visiting and even living in outer space. It was only a matter of time before we had the technology to actually send a man outside of the earth’s atmosphere.

But what did it take to keep a human alive and safe in space? The first living animals launched into space were fruit flies. After that several monkeys, dogs, rats and various other animals were sent and tested upon return. Many of the animals did not survive due to malfunction of the air crafts during re-entry into the earth’s atmosphere along with other mechanical failings. Some died due to atmospheric conditions, like freezing cold. What is known now, is that the two biggest hazards to manned space travel are conditions deadly to humans and unforeseeable malfunctions of the machinery. Humans have adapted to live on earth and to put one outside of its natural environment causes problems. Long term exposure in the microgravity environment of space impacts the body in significant ways.

Radiation, Temperature and Vacuum

Even with the protection of a space suit and the ship itself, solar flare radiation can penetrate living tissue and cause both short and long-term problems with the immune system. Massive ionizing radiation particles emitted from the sun during solar flares are a huge concern. While normally protected by the earth’s atmosphere, an astronaut would be exposed to these solar proton events which can be lethal.

Scientists aren’t exactly certain why, but astronauts suffer from constant elevated body temperatures. A three-month study by NASA finds that in space, a person’s temperature can reach up to 104 °F while exercising. At rest, astronaut temperatures stabilize at around 100.4 °F. Constant high temperatures can affect brain function, cause high blood pressure, problems with circulation and heart attack. “Oliver Opatz, a researcher at the Center for Space Medicine Berlin at the Charité Medical University Berlin and co-author on the study, told Space.com. 'The systems in the body — the blood, the enzymes and the transmitters — don't work as they do when the body temperature is normal. When you have fever, you don't feel well, [and] your brain doesn't work as normal' (Pultarova).

Science fiction films love to portray a gory and exaggerated tale of what happens if an astronaut's body is exposed to a vacuum while in their space suit. The 1981 film Outland has a scene where a man gets a hole in his space suit and his body swells up and explodes. This is not exactly what happens.

The temperature of space is about minus 455 degrees °F. Holding your breath would cause lung damage, and there is a containing effect on your skin so you wouldn’t explode. Heat transfers away from your body slowly, so you wouldn’t instantly freeze. You lose consciousness once all oxygen leaves the brain and when that happens, it’s all over. You will also get a bad sunburn due to exposure to radiation. There is some evidence that he saliva in your mouth could begin to boil. In 1965 at the Johnson Space center, a trainee experienced a leak in his space suit and was exposed to a near vacuum. “He later said that his last conscious memory was of the water on his tongue beginning to boil. So, there's at least one data point about what it's like to be in a vacuum. It won't be pleasant, but it won't be like the movies, either” (Web.archive.org).

Muscle and Bone Atrophy, and Motion Sickness

Weightlessness causes and loss of bone and muscle mass which can increase the risk of injury and permanent damage to the body. Because of the weightlessness of space, a human’s muscles are not required to work as hard, which causes them to weaken and shrink rapidly.

“Studies have shown that astronauts experience up to a 20 percent loss of muscle mass on spaceflights lasting five to 11 days” (Nasa.gov). Bones become frail and share symptoms that resemble osteoporosis particularly in the pelvic region which carries most of the body’s load in Earth’s gravity. Even the heart will atrophy due to it having less blood to pump, and this could cause serious consequences upon returning to earth.

Space Adaption Syndrome, better known as space sickness, rarely lasts over 72 hours with roughly 42% of astronauts experiencing it. The symptoms are vertigo, nausea, vomiting, lethargy and overall uneasiness. With the absence of gravity we become disoriented and the body has trouble perceiving it’s special orientation. Space sickness can even occur after landing back on earth until the astronaut adapts to gravity again.

Blindness, Taste, and the Brain

A NASA study found that space flight causes problems with astronaut’s eyes and vision. This is a concern and is having a major impact on plans for a long-term manned trip to Mars. Abnormalities were found in the eyes of all the astronauts studied, and NASA is still unsure of the cause. “The most common structural change was flattening of the back of the eyeball. Changes in the retina, the light-sensitive area at the back of the eye, and the optic nerve were also found. In some astronauts these changes persisted long after their return to Earth” (American Academy of Ophthalmology). It is the concern that a long trip in space could cause permanent vision damage and even blindness that couldn't be corrected on a long space flight.

No one is sure why, and astronauts will give you different answers, but food can taste different in space. One theory is that in space astronauts will often feel stuffy headed due to blood in the body being evenly distributed instead of it pooling at the legs like on earth. And when you have a cold, sometimes food tastes different. Some astronauts said that the food tasted too bland, and others started to dislike foods they normally enjoyed on earth. Food is preplanned, and if you ask for a ton of food that you now find you dislike, you’re stuck with it for the entire flight.

A 2013 study done on mice shows that exposure to cosmic radiation could speed up the onset of Alzheimer’s disease. The researchers focused their study on iron particles which, due to the force of exploding stars, hurdle through space at accelerated speeds. “The mice underwent a series of experiments during which they had to recall objects or specific locations. The researchers observed that mice exposed to radiation were far more likely to fail these tasks - suggesting neurological impairment - earlier than these symptoms would typically appear”.

Psychological Effects

Sleeping becomes difficult in space. There is constant noise from fans that circulate the air, and astronauts sleep restrained to a bed so they won’t float around. Used to a 24 hour cycle, the body gets cues from the sun rising and setting. In space, it’s difficult to regulate the body’s circadian system which controls sleep, alertness, temperature, organ function and hormone production. Without proper sleep a human is more susceptible to making errors which can become deadly. “On some space shuttle missions up to 50% of the crew take sleeping pills, and, over all, nearly half of all medication used in orbit is intended to help astronauts sleep” (Science.nasa.gov).

Space is a stressful and dangerous environment for several reasons including isolation, mission demands, physical changes in the body and lack of sleep. Add to that: living with people from different cultures, who speak different languages for several months in a cramped, enclosed space. NASA has focused on the mental wellbeing of the crews and astronauts must go through rigorous testing and psychiatric screening. “The agency employs teams of mental health providers, including psychiatrists and psychologists, to support personnel during space missions. Every two weeks, crew members on the International Space Station partake in psychological conferences with medical staff” (Morris).

In Conclusion

Scientists have gained so much knowledge over the 58 years humans have gone into space, and it’s left them with even more questions. In the future, there will be longer treks and more people exploring the depths of our universe. In order to keep a crew healthy, there will have to be medical facilities on board, and there still is little knowledge of how long-term space conditions will effect someone. Scientists at NASA, and even private companies like SpaceX continue to work diligently at solving the problems humans face traveling into outer space.

Humans are natural-born explorers. And through facing the challenges of space exploration, we continue to discover new inventions and industries. We are a curious species and we long to leave something behind for others to find someday.