NASA flight test commander Butch Wilmore (left) and pilot Suni Williams (right). June 5, 2024, Cape Canaveral, Florida, USA
The journey, which was initially supposed to last just over a week, stretched to nine months. NASA astronauts Butch Wilmore and Suni Williams were selected for the first test flight crew on the Boeing Starliner and were supposed to stay on the International Space Station (ISS) for only 8 days, but when NASA discovered several helium leaks and propulsion system issues on the ship, the agency decided to send it back empty until another mission could be sent for the astronauts.
Just imagine being sent on a business trip, even the most ordinary, earthly one, for a few days, and as a result, you get stuck there for nine months. Even in this case, psychologically, it is quite difficult to endure. And if we are talking about a prolonged space flight, then in addition to psychological problems, there are many health threats and unforeseen consequences.
The American site SALON spoke with scientists about the problems that usually arise with astronauts returning from space flights, and what Wilmore and Williams will have to experience when they return to Earth next week.
«IMAGINE HAVING A HUGE GORILLA SITTING ON YOUR CHEST»
After landing, they will be met by a team of doctors who will help them undergo a 45-day post-space rehabilitation program.
NASA's chief flight surgeon Dr. Steven Gilmore believes that during this period, the physiological systems of most crew members recover.
What do astronauts experience?
Firstly, it's the impact of Earth's gravity. When launching into space, the force of Earth's gravity is twice that of Earth. As described by former NASA astronaut Dr. Sandy Magnus: «Imagine having a seventy-pound gorilla sitting on your chest». And after reaching orbit, they will spend the rest of their time in space floating in their seats without experiencing gravity.
However, the effect of Earth's gravity or its absence is just the first thing space does to the human body. People who have been in space have experienced everything from vision deterioration to genetic changes and skin rashes that appeared after landing — even unusual sensations from touching their own clothing...
«When we return, even lifting a pencil will feel very heavy, — said Butch Wilmore in an interview with CNN last month. — This is what returning back is like».
Butch Wilmore sets up a photometer inside the Veggie unit to measure lighting and adjust lighting parameters inside the plant research device
Partly, this is because on Earth, the force of gravity constantly affects the skeleton, stimulating bone-forming cells that maintain our bone density. Without this force, bone and muscle density can atrophy and weaken, and bones become 1% less dense for each month spent in space without any measures taken to combat bone mass loss.
Wilmore and Williams did special exercises in space to mitigate this effect, but scientists believe their bones lost density anyway. For example, astronaut Scott Kelly, who spent a whole year in space, had to learn to walk again.
AGING IN SPACE AND OTHER DANGEROUS CONSEQUENCES
SALON quotes Dr. Afshin Beheshti, director of the Center for Space Biomedicine at the University of Pittsburgh, who notes that the space environment leads to an accelerated model of disease development and an «accelerated aging model». However, he assures that astronauts do not actually age in space, although aging-related phenomena such as cardiovascular risks or cognitive problems accelerate in space.
Scott Kelly participated in NASA's «Twin Study», during which several of his biomarkers were compared with those of his twin brother (Senator Mark Kelly). The astronaut Kelly had more symptoms of heart disease after returning from space than his twin brother, who did not fly to space. In addition, he developed symptoms of the so-called neuro-ocular syndrome associated with space flight (SANS), where blood and cerebrospinal fluid move upwards from the legs to the head without the influence of Earth's gravity, affecting the brain and vision — before the flight, he did not use glasses, but after returning, he started wearing them.
Suni Williams speaks into a microphone during an amateur radio session with students from Banda Aceh, Indonesia
Additionally, disruption of the body's internal clock can affect astronauts' sleep and eating cycles. Some studies have also shown that astronauts' cognitive processing speed in space was lower, although these changes returned to baseline after returning to Earth. But this is not true for everyone. As Professor of Physiology and Biophysics at Weill Cornell Medical Center in New York, Dr. Chris Mason said, — it depends on the individual characteristics of the crew members. Some, on the contrary, start thinking better in space.
Besides, disruption of the body's internal clock can affect astronauts' sleep and eating cycles.
RADIATION
In space, radiation is much stronger than on Earth, as there is no protective ozone layer. For each week astronauts spend on the ISS, the radiation they experience is equivalent to about a year's worth of exposure on Earth, although this can vary depending on the number of solar flares or cosmic rays in space.
Radiation, as scientists have found, affects the mitochondrial function of the cell, which can have consequences for the body, as it disrupts the immune system and circadian rhythms (the body's internal biological rhythms with a period of about 24 hours).
Exposure to radiation is associated with an increased risk of developing heart disease, cancer, and other degenerative diseases affecting vision. The immune system also suffered.
BUT THERE IS GOOD NEWS. THE BODY ITSELF RESTORES DAMAGED DNA
Mason's research also showed that during space flights, several genes related to the immune system are activated, presumably in response to the stress the body is subjected to in such conditions. This happens, according to Mason, to repair DNA. «It's as if the body detects some damage and then repairs it, which is a normal adaptive response». According to Mason, these effects increase the longer astronauts are in space, although about 95% of these cellular changes return to baseline within a few weeks after astronauts return to Earth. For Kelly, 90% of the genetic changes he experienced returned to normal within six months. But, as scientists note, recovery varies among different astronauts and at different times.
CAN RADIATION BE BLOCKED
Scientists have not yet figured out a way to completely block radiation, which interacts with the body in the form of fast-moving invisible particles capable of destroying DNA. However, currently, writes SALON, scientists are testing new small molecules that can increase resistance to radiation in rodents. This could be important not only for protecting astronauts in space but also for patients on Earth undergoing invasive cancer radiation therapy.
HIBERNATION, LIKE BEARS, MAY PROTECT AGAINST RADIATION
The publication writes that other researchers are studying whether artificial hibernation can protect against some of the harmful effects of radiation. Recent scientific papers have demonstrated that stimulating the same process that proteins and bears go through in winter can reduce radiation toxicity.
Dr. Beheshti explains it this way:
«...When radiation damages the body, reactive oxygen species are formed, which affect the immune system and also lead to mitochondrial suppression. But when the body shuts down and goes into a state of hibernation, like these animals, reactive oxygen species stop being produced in such quantities, and then, according to observations, radiation damage decreases...»
Wilmore and Williams will undoubtedly need some time to recover from the long journey, but they have spent years preparing for this, and it seems they are not too upset about having to spend extra time in orbit.
Photo: NASA.