By G. Mudalige, Jadetimes Staff
G. Mudalige is a Jadetimes news reporter covering Technology & Innovation
Spending more than a year in space can profoundly affect the human body. Prolonged exposure to microgravity causes muscles and bones to weaken. Muscles that support posture, such as those in the back and legs, atrophy by up to 30% over time, while astronauts can lose 1-2% of their bone mass every month, risking fractures and requiring years to recover post-mission. Astronauts try to combat this with daily exercise, but even with rigorous routines, it’s hard to maintain muscle and bone integrity.
Microgravity also alters the cardiovascular system, reducing blood circulation to the lower body and causing fluid buildup in the head, affecting vision and sometimes leading to permanent changes. Astronauts often experience swelling of brain ventricles and shifts in neural connectivity, influencing balance, motor functions, and possibly cognitive performance, especially during readjustment to Earth's gravity.
Space travel affects the gut microbiota, with changes in diet and environment leading to shifts in the bacteria and fungi in astronauts' bodies. The skin, exposed to different conditions, may become more sensitive, as seen in astronauts like Scott Kelly, who experienced rashes after his space mission. Exposure to space radiation is another significant concern, causing potential DNA damage, shortening telomeres (indicators of aging), and affecting gene expression related to bone, DNA repair, and the immune system.
These physiological changes highlight the challenges long-duration missions, like trips to Mars, pose for human health and the need for further research into countermeasures.
