Why Living Beyond Earth Is Impossible, Say Astronauts and EngineersNEWS | 08 October 2025One of the biggest problems of living in space or on another world is the unknown. We simply aren't certain of what it will do to the human body because no one has lived in space for longer than 14 months at a time, and only 757 people have ever entered space.
What we do know, so far, is that it's not the healthiest way to live.
Common side effects of long-duration stays in microgravity include muscle and bone loss, decreased blood pressure, and blurred vision. While most of these return to normal once an astronaut is back on Earth, some effects of space radiation — like an increased risk of cancer, cataracts, and damage to the central nervous system — can be permanent.
In all probability, the longer a person remains in space, the worse their health becomes. Even brief trips to other worlds like a return trip to Mars, would take two to three years, and "we just don't have a large enough data sample to understand how that would impact human biology," NASA astronaut Frank Rubio, who spent a US record of 371 consecutive days on the International Space Station, told BI.
He said it took him six months to return to normal after experiencing "puffy head bird legs" syndrome — astronaut slang to describe how the face puffs up and the legs grow thin as your bodily fluids react to microgravity in space.Author: Never Miss A Story. Daniel T. Allen. Enter Your Email. Follow Authors. Source
