MYSTERY WIRE — Astronauts go through rigorous training and testing to ensure they are physically fit. In a way, that has led to some unknowns about how space travel and weightlessness affect an average human body.
Now a study published on Nov. 13 indicates occurrences in several astronauts of reverse blood flow in the jugular vein, and a blood clot in one astronaut. A full report from The Atlantic is posted on Medium.com: “An alarming discovery in an astronaut’s bloodstream.”
Without gravity, the human body does unexpected things:
- We already know that internal organs tend to ascend higher into the body, and there has been concern about constricted blood flow.
- The brain, no longer battling gravity for a blood supply, gets plenty — and concern has risen about elevated blood pressure inside the skull.
- Bloodflow to the lower body is no longer the heart’s easiest task.
- Eyes have tended to flatten in zero gravity.
- Read about NASA’s five known health hazards for astronauts in space.
While a clot is a big concern, it wasn’t easy to detect as blood found ways around it.
Now, with private initiatives to take ordinary people into space, there are wider concerns about health problems never monitored before in zero gravity.
Change the equation for a mission to Mars, and the extremes of gravity become a concern. Even astronauts will have difficulty dealing with the G-forces of a launch, a weightless travel period and a descent over the course of a mission like that.