American astronauts Butch Wilmore and Suni Williams – which was stuck at the international space station for nine months for what was supposed to be a 10 -day trip – are finally Earthbound.
You do not need to be a specialist in rockets to realize that passing the best part of the year in space could have an impact on your health, but what types of changes the pair of NASA can expect their bodies-and could they face long-term repercussions?
Nine months is certainly not the longest that an astronaut has been in space, but Wilmore and Williams can surely expect to live some differences, from their height to their bone density to their eyeballs.
Height
One of the most surprising effects of microgravity is that astronauts become larger in space – sometimes up to two inches. Without the constant drop in gravity, the vertebral discs develop, increasing the overall height.
However, this change is temporary.
Once back on earth, the vertebral column is compressed again, which generally returns the astronaut to their usual height. Astronaut Scott Kelly Lost the almost two inches in the height he won during his record stay of 340 days at the international space station after only two days back.
Bone
The prolonged time in space leads to a significant loss of bone density.
Without the usual stress of gravity, bones – especially in promising areas such as hips and legs – begin to lose minerals, which makes them lower.
According to at NASAAstronauts lose between 1% and 1.5% of bone density in these areas per month in space.
Loss of bone density – also known as osteoporosis – can lead to several health complications, including an increased risk of fracture and fall, reduced mobility and chronic back pain.
Muscles
Muscle atrophy is another common problem in space missions. Shenhav Shemer, professor of biology at Technion – Israel Institute of Technology, Tell Axios That the muscles are likely to gradually weaken, the more the astronaut is in space.
She added that women are generally more at risk of atrophy and bone loss because they naturally have less muscle mass and testosterone and can undergo other hormonal changes in zero gravity – which means that Wilmore and Wilson can be affected differently.
According to at NASAAstronauts must exercise at least two hours a day on a treadmill or a stationary bike to avoid bone and muscle loss.
“Without this exercise, they could not walk or get up when they return to earth after months of floating in space,” they wrote.
Vision
Many astronauts come back to earth with vision problems due to neuro-occurrence syndrome associated with space flights (SAN).
Although the exact cause is always sought by scientists, a theory is that the lack of severity modifies the distribution of fluids in the body, resulting in increased pressure on the optic nerve and the changes of ocular shape – the eyeballs can become flattened and the optic nerve can swell, leading to a reduced vision and an altered blood flow.
“The structural changes of the brain seem weak but seem to indicate that more than half of the crew members have one or more symptoms of without”, NASA wrote.
While some of these problems may persist for years, no crew member reported Significant or permanent vision loss following a mission so far.
Hearts
Because it does not have to work so hard to pump blood against gravity, the heart can become slightly smaller and less effective in microgravity.
This can cause low blood pressure and dizziness when astronauts return for the first time to earth.
Research suggests that this effect is temporary and Some studies Displaying astronauts generally have better cardiovascular health than the general population of the earth.
Balance
Microgravity affects the vestibular system, the inner ear structures responsible for balance.
After months of floating, astronauts may need to adapt to the shock of gravity and to feel bank and disoriented accordingly – a phenomenon called “space legs”.
Risk of cancer
Astronauts are exposed to more radiation outside the protective atmosphere of the earth, thus increasing their global Risk of cancer.
Wearing a dosimeter and other protective measures can help alleviate this risk, that NASA aims not to maintain more than 3% more than the general population.
‘Little things’
With everything we know, there are still things that you cannot predict.
“The big things you expect, right?” Be disoriented. Be dizzy ”, Matthew Dominick said at a press conference After spending a long stay aboard the ISS. “But the little things, like just seated in a hard chair, right? My back didn’t really sit in a difficult thing for 235 days.”
“Everyone is different. And this is the part you cannot predict,” said Jeanette Epps, another astronaut from the same mission.
“A problem that Matt can have, I may not have, but I may have several things that he does not have. And so, and we have had different experiences on board. So we don’t know how we are going to react when we come back and at what speed. And every day is better than the day before. “