The pull of the cosmos is irresistible, but the human body seems to think differently. In space, far from Earth, there are insidious dangers for our health: scientific research is finding more and more of them.
The conquest of space, which has always been a dream of humanity, collides with a crude and indisputable physical reality. Which? The human body is not made to live outside the Earth's atmosphere. Our organism, which evolved in the context of Earth's gravity and oxygen-rich atmosphere, encounters serious difficulties when exposed to the space environment.
Human body, the challenge of zero gravity
The first and best known effect of a prolonged stay in space is the loss of bone and muscle density. In the absence of gravity, muscles and bones, no longer as stressed as on Earth, tend to weaken. Astronauts must undergo rigorous exercise programs to counteract this phenomenon, but despite this, returning to Earth is often marked by a period of rehabilitation.
A NASA paper published in Nature (here it is) explains that in the microgravity environment of the International Space Station, bones and muscles do not have to support the mass of the human body, leading to their loss or atrophy without terrestrial exercise. The research describes how microgravity-induced bone loss is a significant and unresolved risk for space travelers, increasing the likelihood of fractures and kidney stone formation.
Unexpected “problems”.
Among other insidious problems related to space travel there is the erectile dysfunction. A study on FASEB Journal (I link it here) associates exposure to high levels of galactic cosmic radiation (GCR) and microgravity during space missions with an increased risk of oxidative stress and endothelial dysfunction.
In their methodology, the research team subjected 86 rats to a four-week regimen that simulated space conditions at the NASA Space Radiation Laboratory. Follow-up exams conducted 12-13 months later assessed long-term damage.
The results? They reveal a previously unrecognized health risk: a prolonged deterioration of neurovascular erectile function that may affect astronauts' sexual health for the rest of their lives after they return from prolonged space missions.
Goodbye nails
Many astronauts they lose their nails after spacewalks, a phenomenon known as onycholysis.
According to an article in National Geographic (I link it here), sustained pressure on fingertips during extravehicular activities (EVA) causes intense pain and loss of nails in cosmonauts. The loss of circulation could explain the falling off of the fingernails and suggests that customized or new gloves with robotic joints could be the solution for astronauts.
Human body and space exploration: research continues
Astronauts aboard the International Space Station (ISS) are living experiments for scientists on the ground as they seek to better understand the effects of space on the human body. This research is essential to prepare for future missions.
There are many things to work on, but if you want my opinion, a good part of the efforts should be concentrated on spacesuit design, which in space missions should be considered the real second skin for a human body. A crucial role is played on this level, as you have read. The challenge is to create suits that protect astronauts while maintaining their health and physical function. Not easy.
Towards new frontiers
Despite the obstacles, space exploration continues to be a priority for agencies like NASA. The Artemis program, which plans to return humans to the Moon, and missions to Mars in the 30s are examples of how human ambition pushes the limits of the body.
Our presence in space remains a fascinating and challenging field of study. Astronauts who travel in space are not only explorers, but also pioneers of a new understanding of the human body and its capabilities.
The road to the stars is fraught with challenges, but our thirst for knowledge and our determination to explore will push us further and further. Hopefully with all the nails (and family jewels).
