The human body faces difficult health conditions in space, including loss of a percentage of muscle mass, heart problems, and kidney stones, but it recovers almost completely three months after its owner returns to Earth, as shown by about 20 studies conducted on space tourists, the results of which were published in the journal ” “Nature”. However, if the trip is to Mars, the person may need dialysis upon returning to Earth.
At a press conference, Christopher Mason of Weill Cornell Medical College in New York, the lead author of one of the studies, said, “This is the most in-depth research we have ever conducted on a crew.”
Understanding the health impact of spaceflight is important for future manned lunar missions, as well as for the space tourism industry, which hopes to send anyone who can afford it into orbit.
Researchers from more than 100 institutions in the world checked all the data related to the health of 4 space tourists who participated in trips organized by SpaceX, as they spent 3 days in orbit in September 2021 without any professional astronauts.
The number of these people is small compared to the approximately 700 people who have visited space since the beginning of space exploration. But governments were not always willing to share data on their missions, according to Afshin Beheshti of NASA, one of the scientists who prepared the study.
The four Americans from the Inspiration 4 mission did not hesitate to undergo a set of tests. The results were widely circulated and compared to the results of tests conducted on 64 other astronauts.
The astronauts’ bodies suffered changes in various organs: heart, skin, proteins, kidneys, genes and cells.
Safe going to Mars
Manned flight is likely to lead to loss of bone mass and problems with the heart, eyes, kidneys and other organs. But about 95% of these health indicators return to normal levels within 3 months of the person returning to Earth, according to Christopher Mason.
Mason hopes that these results will help scientists identify medications or measures needed to better protect crews.
The Inspiration 4 mission, funded by its leader, billionaire Jared Isaacman, wanted to prove that space is available to people who have not spent years training before participating in a space flight.
One study showed that the telomeres, the ends of the chromosomes, of the four crew members expanded significantly in orbit. But during the months after their return to Earth, the telomeres returned to their original length.
Since telomeres also lengthen with age, finding a way to solve this problem may help combat aging, according to Susan Bailey of Colorado State University, an author of one of the studies.
Given the data collected to date, “there is no reason why humans could not get to and back from Mars safely,” Mason said.
He said, “It is likely that we will not make many flights, given the large amount of radiation.”
One study showed that mice exposed to radiation equivalent to 2.5 years in space suffered permanent kidney damage.
“Even if an astronaut can go to Mars, he may need dialysis upon his return to Earth,” Keith Siu of the London Topical Center said in a statement.
Another study indicated that female astronauts bear more stress resulting from spaceflight. “This could be explained by the fact that women are having children and their bodies are more accustomed to big changes,” Mason said.