Understanding Humans in Space
What spaceflight does to the human body, how a crew is kept alive, and how their health is protected on the way to the Moon and Mars. Built on real NASA/ESA human research; quantitative figures are omitted unless well established.
Related entities
- Space-biology discipline
Space Medicine
The medical discipline concerned with keeping astronauts healthy before, during, and after spaceflight — studying how microgravity changes the body and how to protect it on long missions to the ISS, the Moon, and Mars.
- Space medicine
Bone density loss
In microgravity the human body loses bone mass, a key concern for long-duration spaceflight that is studied and countered aboard the ISS.
- Countermeasure
Resistive Exercise
Weightlifting in orbit. Devices such as the ISS's Advanced Resistive Exercise Device let crews load their bones and muscles against a resistance in place of gravity — the single most important countermeasure against bone and muscle loss.
- Life-support technology
Water Recovery
On the ISS, most of the crew's water is recycled — reclaimed from humidity, hygiene water, and urine and purified back to drinking quality. Closing the water loop is essential to missions too far to resupply.