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This is How Spaceflight Affects the Human Body

This is How Spaceflight Affects the Human Body

As our technology advances, spaceflight for the average human is becoming more of a possibility. As exciting as this is, there are things we should know about how space travel affects us.

Spaceflight affects the human body both physically and psychologically. The main ways that the body is affected are:

  • Muscle atrophy
  • Bone loss
  • Disorientation

The effect of space travel on humans has been under research for more than 50 years, so that certainly isn’t the extent of the effects.

So, how does spaceflight affect our physical and mental health? We want to know this and why it happens. This article will discuss these undesirable effects on the human body and how to reduce or eliminate these problems.

How Does Spaceflight Affect the Human Body?

The effects of spaceflight affect nearly every organ in the body. Leaving Earth is very stressful on us physically and mentally. This is part of the reason astronauts must go through rigorous training before going on a mission.

The article from Touro Scholar briefly talks about many of these effects.

 Here is a list of symptoms the body is at risk of experiencing in spaceflight:

  • Loss of consciousness
  • Rapid bone degeneration
  • Calcium Kidney Stones
  • Expansion of the vertebrae of the spine
  • Swelling of the face
  • Swelling of the brain
  • Anemia
  • Farsightedness
  • Lowered immunity

These are just a few of the physical effects of spaceflight on the human body. Let’s discuss these symptoms further as we examine why they occur.

How does Spaceflight Affect the Bones of the Human Body?

Spaceflight affects the skeletal system. On average, a person will lose 1 to 1.5 percent of mineral density each month while in spaceflight. This bone loss is not regained and can continue to progress after returning to Earth.

Though there are weight-bearing exercises that astronauts are expected to perform while in space, these do not entirely combat the effects of bone loss in astronauts. The vertebrae of the spine will also experience deformation as it elongates. The intervertebral discs suffer structural loss and function loss.

How Does Spaceflight Affect the Muscles of the Human Body?

Spaceflight causes muscle atrophy. This is an extreme weakening as well as loss of muscle mass. Astronauts lose up to 20% of their muscle mass in microgravity flights that last from 4 to 11 days.

They lose muscle because they do not need to work as hard outside of Earth’s gravitational pull. The muscles in the back along the spine especially weaken. As they weaken, the bones of the spine also become stiff and straightened.

NASA requires strenuous exercise of astronauts for two and a half hours every day while they are in microgravity. This may not be enough, though, as many astronauts still experience back pain after returning to Earth. Even with rebuilding the atrophied muscles, back pain persists.

How Does Spaceflight Affect Blood Supply in the Human Body?

Blood supply is affected in spaceflight because the heart muscle is affected. The heart changes shape, becoming more rounded and less oval. Due to the heart not being able to constrict as well as it does on Earth, our bodies cannot regulate how much blood is pumped through the body.

This causes orthostatic intolerance in some astronauts that have returned to Earth. The blood and fluids rush back into the lower extremities and cause dizziness and weakness, preventing the astronaut from being able to stand.

How Does Spaceflight Affect The Brain?

Spaceflight affects the human brain causing a loss of consciousness while exiting Earth’s gravitational pull. While our bodies experience microgravity, the brain is subject to swelling due to cerebral pressure. This is because the fluid in our body can suddenly move from our lower extremities as we experience weightlessness.

The effects that are experienced may last even after returning to Earth, as various studies have shown. Of these, macrostructural changes have been observed, such as:

  • Changes in brain position
  • Tissue volume
  • Distribution of cerebrospinal fluid

These effects are also noted as becoming more pronounced the longer the spaceflight mission lasts.

Image Via NASA

How Does Spaceflight Affect Humans Psychologically?

Spaceflight can cause an array of psychological factors in humans. Going into space and experiencing microgravity, as well as being in a small enclosed space for long periods, can cause people to experience stressful and difficult emotions.

This chart shows how the central nervous system is affected during spaceflight.

Emotions that may be experienced are:

  • Insomnia due to disruption of circadian rhythm and the effects of blue light
  • Irritation
  • Fear
  • Depression
  • Loneliness

All of these have been observed and reported by those in spacelight. It is believed that many of these emotional responses are due to emotional stimulation humans have experienced on Earth, as these symptoms usually begin to alleviate as the mission progresses.

However, heightened emotions have also been noted to escalate ¾ into a mission before falling back to more normal levels. As the spaceflight mission draws to an end, astronauts generally experience feelings of euphoria and joy.

The Effects of Spaceflight on the Human Body

The effects of spaceflight on the human body are numerous. It is a stressful environment at a cellular level, as the physical body enters survival mode in an attempt to adapt to this foreign environment.

Those experiencing space travel are subject to radiation, which can also have harmful effects on the human body. Even though these effects have been under examination for more than 50 years, experts say there is still much to learn.