Climate change, war and fascism got you down? Wish you could buy a ticket on the Europa Clipper spacecraft that’s on its way to check if there’s living slime on a Jupiterian moon? Before you decide to leave Earth behind and move to outer space, consider the life of an astronaut on the International Space Station.
Imagine cohabitating with eight other people in an enclosed area the size of a large airplane. You live on a strict schedule broken into 15 minute increments, using a red marker on a computer tablet to keep pace with the daily routine of experiments and maintenance all on an average six hours of sleep. You never shower, and instead rely on wet wipes for personal hygiene. Every human odor remains trapped around you in a cloud of stench that U.K. astronaut Tim Peake has compared to “a barbecue that’s gone wrong.” You drink processed urine. Things only get more uncomfortable from here.
Stranded NASA astronauts Sunita Williams and Butch Wilmore have been living aboard the ISS for 170 days since their departure from Earth on June 5. Their mission, originally meant to last around a week, will have gone on for over eight months by the time the two are picked up by a SpaceX Dragon at the end of February 2025. NASA’s accepted odds for loss of crew during the extended stay, or the chances Wilmore and Williams won’t make it back to Earth alive, are 1 in 270. Although chances of death on their mission are relatively low, the effects of their long term stay in space will likely have an impact on their bodies for the rest of their lives.
To get a better idea of how the unexpected extra months in space may impact Williams and Wilmore, Salon interviewed NASA’s lead flight surgeon, Dr. Steven Gilmore, who supported Captain Scott Kelly during the longest planned space mission in NASA’s history: 340 days. While one mission was going on in space, another was conducted down here on Earth. NASA was monitoring changes in Captain Kelly's body while comparing to his twin brother, Mark, now an Arizona senator, who remained on the ground during the experiment in order to determine the effects microgravity has on humans over extended periods of time.
“Essentially you can look at each of the body systems and start quantifying and characterizing the changes that the human body goes through [in space] as it's in this different environment for longer and longer periods,” Gilmore said.
It’s easy to forget the joys of gravity while going to sleep or using the toilet on Earth, but the constant force that keeps us on the ground also helps us maintain bone structure and keep bodily fluids flowing where we want them. Living in microgravity causes bodily fluids to become more evenly distributed, with up to two extra liters of blood becoming unnaturally congested in the upper body, triggering constant feelings of puffiness and congestion, especially in the head and face. In Captain Kelly’s memoir, “Endurance: A Year In Space, A Lifetime of Discovery,” he describes the feeling of “space brain,” writing, “The full head sensation never completely goes away. It feels a little like standing on your head 24 hours a day, mild pressure in your ears, congestion, round face, flushed skin.”
The way fluids redistribute themselves in space is also why astronauts can’t burp without throwing up — the contents of their stomach become evenly pressed to the sides of the organ instead of settling at the bottom. This effect also causes urine to float along the sides of the bladder, which can prevent astronauts from feeling a need to pee until their bladders become completely full, leading to an unexpected, spontaneous need to urinate.
Reduced pressure on the urinary sphincter is one of the many sensations dulled by living in microgravity, along with smell, taste and sight. Increased pressure from redistribution of fluid in the nose inhibits nerve endings in nasal passages, reducing the ability to smell and taste — one reason why wasabi and hot sauce are popular condiments on the ISS. Additionally, around 70 percent of astronauts who conduct long-term missions of six months or more on the ISS develop vision impairments. Although the actual cause of loss of vision in space is unknown, in theory an increased volume of fluid inside the head causes choroidal folds in the eyes, causing blind spots. Dr. Gilmore added that this condition can also change a crew member’s eyeglasses prescription — they may be 20/40 in the same glasses that they were 20/20 in on the ground, for example.
“We've observed it enough that our optometrists can estimate before they fly by what degree their prescription will change,” Gilmore said, adding crew members are often equipped with “space anticipation glasses” from the outset of missions in order to help them see after weeks or months in orbit.
Besides the redistribution of fluid in the body, changes made to the skeletal system by living in microgravity can cause longer-term health consequences. Without the constant pressure of gravity on the skeletal system, calcium from bones leaches into the body, which besides weakening the bones themselves can lead astronauts to be at higher risk of developing kidney stones.
“The [bodily] response without that gravitational input is to start reabsorbing bone because it's perceived that they don't need it,” Gilmore said. “The bone isn't having to support all the muscular structure and ligaments that are working against gravity.”
This lack of gravity can cause astronauts to grow as much as 3% taller while in space as their skeleton realigns, then later shrink to their original height after returning to Earth. Bone density may reduce around 1% for each month spent in space, and NASA-funded research has shown that bone strength, a separate metric, may drop up to 5% each month. Risk of death from hip fracture increases with age, making bone loss one of the most significant long-term dangers of extended space missions.
To offset the loss of bone and muscle while living in zero gravity, astronauts routinely exercise for two hours every day, six days a week. On her initial mission aboard the ISS, Williams, one of the astronauts currently stranded, became the first person to complete a marathon in space, remotely participating in the 2007 Boston Marathon, finishing in 4 hours 24 minutes. Besides training on treadmills, the crew also uses stationary bicycles and other specialized equipment that relies on springs and vacuums to create resistance. Williams also became the first person to complete a triathlon in space during her second mission in 2012, using a strength training machine in place of the swimming portion of the event.
Some impacts of life in space can’t be fixed through exercise. Astronauts on the ISS encounter high levels of radiation — equivalent to roughly 10 chest x-rays every day, or around 30 times the amount of radiation people on Earth experience on a daily basis. This has an impact on a cellular level, and can even lead to an increased risk of cancer. Astronauts typically undertake two or three missions throughout their entire careers, and NASA aims to limit radiation exposure so that no crew member develops more than a 3% increased risk of cancer.
Discoveries made during NASA’s study on the Kelly twins found extended time in space also impacts telomeres, the protein structures at the ends of chromosomes that control cellular division. After spending almost a year in space, Scott Kelly’s telomeres had actually lengthened, which is usually an indicator of good health and lower odds of age-related diseases. However, during the months after returning to Earth, the length of his telomeres were discovered to be critically shorter than his preflight levels.
Despite all the unpleasant ways life in space may change the body, these long-term effects do not appear to concern Williams, who insisted in a recent Instagram post, “I love being up here in space.” However, this isn’t the first time Williams has been stranded. When Williams first visited the ISS in 2006, she had to stay over 6 months longer than originally planned after the return shuttle intended to take her home was damaged by hail before it could take off from the launch pad in Florida.
Besides sticking to a strict exercise schedule, living and working in space requires maintaining morale and mental health. Salon also interviewed Dr. Suzanne Bell, who leads NASA’s behavioral health and performance lab, which supports ISS crew members during biweekly psychological evaluations and researches ways to enhance coordination at all stages of space missions. Bell works to find countermeasures that relieve stress for astronauts and improve teamwork.
“One of our most important countermeasures is astronaut selection. 20,000 people apply and we only have space for 8 to 12,” Bell said. While only the most elite candidates are chosen to go to space, NASA’s behavioral health program works to optimize their emotional support system by keeping them connected with their loved ones on Earth.
“What we know from ISS astronauts is that communication with their family is actually one of their strongest coping mechanisms for difficulties in space, so that real time connection with friends and family is an important coping source,” Bell said.
Astronauts aboard the ISS can initiate telephone calls to loved ones, but can’t receive them. There is also an approximate one second delay in information as it goes between Earth and the ISS, slowing down the pace of conversations astronauts have with their loved ones on Earth. Crew care packages are another way NASA supports morale, and in the past have included items ranging from musical instruments, different kinds of food, books and religious items, as well as a gorilla suit.
“It can be an important boost when you’re living in that austere environment that no longer has the smells of Earth,” Bell said. “Even something simple like an orange or your favorite chocolate bar, when you have that fragrance, when you have that special thing you worked with your family to send, it’s a really substantial morale boost.”
Williams is carrying fish curry and a Ganesh statue, along with tags from her two labrador retrievers and multicolored socks. Wilmore’s personal kit includes a set of gold rings designed with emblems resembling the U.S. Navy astronaut badge, as well as college memorabilia from Tennessee Technological University and the University of Tennessee, his former schools.
Spending longer amounts of time in space helps prepare astronauts for future missions that will leave them even more isolated as they travel farther from Earth. Surviving extended time in space by years, or even human generations, will be necessary for longer term missions to Mars and beyond, and astronauts will need to become more comfortable with spending time in isolation. Instead of dealing with a one second communication lag to Earth from the ISS’s current position, Bell went on to explain that a potential mission to Mars would create a 44-minute delay to send and receive messages between planets. Other than the Moon, the closest thing in our neighborhood isn’t that close.
“Everything we look at for going to Mars requires crews to be autonomous in their problem-solving and peer support,” Bell said. Current plans for a shuttle to Mars would require a crew of four people to share a much smaller living area than the ISS for a round-trip that would take 21 months.
In preparation for almost anything, standard gear on the International Space Station today includes an early pregnancy test and a body bag. However, as missions are planned for Mars and beyond, NASA is looking into ways of stripping down as much equipment as possible. In contrast to the growing space tourism industry, such as the orbital movie studio planned to open this December, as well as plans to host the first Michelin star meal in space next year at a cost of nearly half a million dollars per guest, the future of research on how living in space impacts human anatomy is uncertain. The ISS is scheduled to be retired in 2030, at which point NASA plans to transition to commercially-owned space stations in low Earth orbit.
If you are planning a trip to space as your next luxury vacation, prepare to be trapped in a tiny room that smells like burning farts, along with many more serious health consequences you might encounter as your body adjusts to a completely new environment. For astronauts like Williams and Wilmore, the impact space has on the body is a small price to pay to explore the solar system. For those of us who haven’t been to space yet, health conditions caused by living in microgravity can be a reminder of how relatively comfortable life is here on Earth.
