Space is a dangerous place. Gravity, radiation, and isolation all pose unique health risks. Astronauts’ health is therefore a top priority from the time they’re selected until well after their final mission. Doctors, scientists, technicians, engineers—and even the astronauts themselves—work together to support the health of those working in space. Cooperation is critical for the success of both current missions and future deep space expeditions. What they learn can also help solve medical challenges on Earth.
In the following videos, retired astronauts Dave Williams and Robert Thirsk—and current astronaut David Saint-Jacques—present and discuss the unique health challenges of living and working in space. Not only do these men have first-hand experience orbiting Earth, they are also medical doctors who bring a unique understanding to the topic of health in space.
These videos were created in collaboration with the Canadian Space Agency. You can explore these, and many more, when you visit the Health in Space exhibition—either onsite at the Canada Aviation and Space Museum, or on the road in a city near you.
Health in Space: A Canadian Perspective
In this introductory video, Dave Williams and Robert Thirsk discuss Canada’s leading role exploring health in space.
DW: Dave Williams
RT: Robert Thirsk
For many years, Canada has specialized in an area of medicine called Space Medicine. It discovers how humans adapt and work in the unique environment of space, and the lessons that we've learned in the past will help us get ready to send humans beyond Earth orbit, going farther, and staying longer in space.
Canada plays a major role in the establishment and the advancing of space medicine. The Canadian Space Agency has four active astronauts. So, Canada has a responsibility, number one, to maintain the health, the wellbeing of these astronauts so that they can be productive and fit for duty in space. Secondly, the Canadian Space Agency and Canadian scientists participate in breaking down the frontiers, the barriers to space exploration. In Canada, we have expertise in a number of areas: radiation, dosimetry, the psychosocial aspects of living in an isolated and confined environment, and cardiovascular and vestibular physiology as well. So, we're making contributions to our national program, and also to the international endeavour to explore the inner solar system.
Variable gravity impacts the human body in many ways. Robert Thirsk discusses the effects of gravity on human health, sharing how he faced vision issues while serving in space.
It's probably true to say that every single organ system in the body is affected some way by the space environment, particularly by weightlessness. I experienced a lot of the common medical issues that astronauts who flew prior to me had also experienced—so, for example, space motion sickness, fatigue due to my deconditioning cardiovascular system. One syndrome that I experienced that was atypical was visual problems. About a month after I arrived on orbit, I found that I had difficulty reading books and manuals that were provided to us. My distant vision was fine, but my close-up vision was not. So, over a series of months, we investigated my eyeballs, my visual acuity—looking at the back of the eyeball, looking at the optic nerve out of the back of my eyes that ran to my brain—to try to determine what was going on. We learned that there were signs of raised intracerebral pressure—that is, the pressure that's bathing my brain was compressing my eyeball. So, that was very unusual. I was one of the first astronauts to ever experience that visual syndrome, but since I flew, several other astronauts have had a similar visual problem.
Health and Radiation
Astronauts are exposed to increased levels of radiation outside of Earth’s protective atmosphere. Robert Thirsk discusses how technologies help to manage these risks.
Aboard the Space Station, astronauts are subjected to higher levels of ionizing radiation than we are on the ground. Therefore, we need to take special precautions. First thing we do is we all wear personal dosimeters, which are radiation monitors, on our body throughout the day, 24 hours a day, to monitor how much radiation we are receiving. We also place similar radiation dosimeters throughout the Space Station structure as well to see which parts of the Station are more susceptible to higher fluxes of radiation and which ones are susceptible to lower doses.
Secondly, we try to shield ourselves, as much as possible, from the incoming radiation. For example, I slept in two different areas during my six months aboard the Space Station. The first area where I slept, I surrounded my sleeping bag with bags of water. We know that water is a relatively good shield against incoming radiation. So, I was sort of sleeping inside a cocoon of water bags. Later, I moved into a sleep station, which is a compartment roughly the size of a telephone booth, and all of the walls of that sleep compartment were lined with panels of polyethylene. Polyethylene contains a lot of hydrogen atoms in the structure of the polyethylene molecule, and that's also found to be very protectant against radiation.
Finally, in the event that there was a major solar flare—and there was not a flare during my six months aboard the Space Station—the crew would all head to the rear end, or the aft end, of the Space Station—to the Russian end—where there's a lot of equipment. It gives us a little bit more shielding against radiation in that back area, but it's still not perfect. But it is what we would call a "storm shelter" in the event of a radiation storm.
Mental Preparation and Training
Working in an isolated environment—orbiting 400 km above Earth—comes with many unique stresses. Robert Thirsk and David Saint-Jacques share how in-depth astronaut training mentally prepares astronauts to face these challenges.
DSJ: David Saint-Jacques
RT: Robert Thirsk
Everybody knows it’s easy to be a nice guy when everything is going well, but what really matters is: who are you when things are difficult, when there are problems? That stuff really matters, and nowhere else does it matter more than on board a spacecraft should there be an emergency. We want to be up there with people who keep their cool, who keep thinking about others, who keep the overall mission and the team in mind when they’re making their decisions, despite the strenuous circumstances.
The first thing that we do to try to promote that kind of environment is select astronauts carefully. We’re looking for astronauts who have got a lot of experience working as team members. We’re looking for astronauts who have certain soft skills or non-technical skills, like self-care, self-management, group living, teamwork, collaboration, cross-cultural sensitivity. I was blessed during my six months in space, and we had a wonderful time. If you look at some of the photographs or some of the video of my crew in orbit, we all have these big, goofy grins on our face because we got along well together, and we knew about how to manage any personal conflicts that might arise.
We maintain these skills by joining expeditions in difficult, dangerous, or remote locations in the Arctic, in the desert, underwater, just so that we can practice our group living, decision-making, negotiations, survival skills, ingenuity—all these things that are required to be a good expedition crew member and, ultimately, have a successful space flight.
Space: A Childhood Fascination
David Saint-Jacques shares how his childhood curiosity, and a life-long love of learning, sparked his fascinating career as an astronaut.
My fascination with space began as a young child when I saw these images of the Earth, seen from space. I was fascinated by the beauty of our planet, by its obvious fragility, and by the fact that someone had been there to take that photo. Somehow, that was mind-blowing, this new perspective. As I grew up, I kept that image of space exploration as a fantasy. As a young boy, I was always playing at being an astronaut, deciding to become an explorer, an adventurer, maybe one day even a scientist. Then, later on, when I came to choose what to do at university—I went into science—I kept somehow modelling myself on astronauts. I never thought it was possible. Nobody thinks becoming an astronaut is possible. Lo and behold, I got super, super lucky and did become an astronaut, and now I have to live up to the expectations.
Health and Future Exploration
Robert Thirsk and Dave Williams consider the future of human space travel—long duration missions—and explore the health-related advances necessary to propel humanity further than ever before.
RT: Robert Thirsk
DW: Dave Williams
I’m really excited about the future of human space travel. For the last 17 years, since 2000, we’ve had humans living and working permanently on board the International Space Station. That’s an absolutely incredible feat, working on the most complex piece of technology ever built in the history of the human species. It’s time to go beyond Earth orbit, to go farther, to stay longer. Where are we going to go? Could be back to the moon. Could be sending humans onto Mars. The myriad of issues that astronauts are going to face with how their body adapts to functioning in the microgravity environment while we’re going to our destination—how the human body adapts to, whether it’s the 1/5th gravitational environment of the Moon, or the roughly 40% gravitational environment on the surface of Mars—is something that we’re going to need to learn to study to be able to enable humans to become what I might call “a space-faring species.”
What’s exciting for me is that humanity will soon be leaving low Earth orbit and heading further into the solar system and into deep space. That will have implications for the healthcare of astronauts. For deep space missions, I expect, for example, that radiation monitoring will become paramount. Also, we can expect some psychosocial implications of living in an isolated and confined environment far, far, far away from Earth, family, and nature. I also expect that the way that we administer healthcare for deep space astronauts will change. Aboard the Shuttle, aboard the International Space Station, we can depend on re-supply of medical consumables from the ground. We can depend on communication with our Flight Surgeon and the rest of the healthcare team to help us through some medical situations amongst the crew. We can’t on deep space missions. It may take, in some situations near Mars, 20 minutes for me to report a medical emergency before the Flight Surgeon on the ground will hear my voice to say that there is an emergency situation. So, therefore, we need more medical independence aboard a spacecraft—perhaps robots, perhaps artificial intelligence that will be able to guide astronauts through the diagnosis and treatment of medical maladies aboard a spacecraft, particularly for emergency situations.