Surviving Space: The Impact on the Body and How Astronauts Recover

Living in space is not an easy task for human as well as their body. Spending time in microgravity, where there is little gravity like on the International Space Station (ISS), can cause different health issues. Here's how being in space harms the body and how astronauts recover when they return to Earth.

Muscles and Bones: In space, there is no gravity pulling on the body, so astronauts don’t use their muscles and bones as much. This causes their muscles to shrink and their bones to become weaker. Astronauts lose about 1% of their bone mass every month. This is like aging a whole year on Earth. They also lose around 20% of their body fluids and 5% of their body weight.

Radiation: In space, astronauts are exposed to much higher levels of radiation than on Earth. While the ISS is protected by Earth's magnetic field, astronauts still face more radiation during long missions. This can increase their risk of getting cancer and cause damage to the brain, which could lead to problems like Alzheimer's disease.

Eyesight and Skin: Astronauts can experience vision problems in space because of microgravity. They are also at a higher risk of cataracts. Their skin becomes thinner, more fragile, and takes longer to heal.

Immune System: The immune system of astronauts becomes weaker in space. This makes them more likely to get sick. The lack of gravity can also affect blood circulation and slow the production of red blood cells, which can lead to problems with the heart.

Body Fluid and Weight: In space, body fluids shift to the upper body, making astronauts appear “puffy” in the face. They also lose weight because of muscle loss.
 

Psychological Effects: Spending long periods in space can also affect astronauts mentally. They may feel disoriented, experience motion sickness, and have trouble sleeping. Radiation can even affect their brain and lead to problems with thinking and memory.

How Does the Body Recover After Returning to Earth?

When astronauts return back to Earth, their bodies need time to adjust to gravity again. In the first few days, they may feel dizzy, have trouble balancing, and be tired as their cardiovascular system gets used to gravity, with their spine also returning to its normal size. After a week, motion sickness, disorientation, and balance problems go away, and their sleep patterns improve. 

In two weeks, their immune system begins to recover, and they regain the body fluids and red blood cells lost in space. By one month, their muscles start to rebuild and feel stronger. After three months, their skin and eyesight return to normal, and they regain most of their body mass. However, even after six months, their bones remain weaker, and they still face a higher risk of fractures and cancer, with about 7% of their genes still affected.

Living in space is tough on the body. It weakens muscles, bones, and the immune system, and astronauts are exposed to harmful radiation. While the body starts recovering once they return to Earth, it takes time. Some health issues, like weakened bones and higher cancer risks, can last long after coming back home. But with exercise and medical care, astronauts can gradually regain their health and return to normal life on Earth.