A sizable portion of humanity recently spent many months in various stages of pandemic lockdown – usually inside their homes performing work tasks online while rarely venturing out of their protective cocoons into the outside world. When the lockdown was over and some ventured out their doors, they found that the world had changed – traffic was different, the work environment was different, even the formerly polluted air was different – and so had their bodies. Humans found they had gained weight and were out of shape due to inactivity – even if they rode their exercise bikes and followed their online trainer (or at least pretended to). In a way, we performed a simple test simulation of what might happen to astronauts spending months in a spacecraft on a mission to Mars … never leaving their abode, performing limited work and physical activities, not knowing how their bodies would react in the changed world they would eventually enter. If our little lockdown simulation had such a major effect on our bodies, what will happen to the astronauts? Some researchers fear they will collapse, faint or suffer a major medical trauma when they take the next one small step for man, one giant leap for mankind onto the Red Planet. To find out, a team of space medicine experts developed a model and sent it on a simulated Martian voyage. What happened when the model landed on Mars? Did it find out it had gained too much weight to fit into its spacesuit and spend another month working out?
“We know it takes about six to seven months to travel to Mars and this could cause the structure of your blood vessels or the strength of your heart to change due to the weightlessness experienced as a result of zero gravity space travel.”
Most stories about problems astronauts will encounter during a voyage to Mars focus on the constant bombardment of cosmic radiation and how to protect them from it. Dr. Lex van Loon, a Research Fellow from The Australian National University (ANU) Medical School, decided to focus on a lesser yet still serious problem – the effect of microgravity on the human body for seven months and the changes it could make to the cardiovascular system. While we know how astronauts react to a return to Earth gravity after months in microgravity on the International Space Station, we don’t know what will happen on Mars, where the gravitational force is less. Since there is no “vomit comet” airplane to physically simulate Martian gravity, a simulation would have to do. Van Loon assembled a team at ANU to create one.
“With the rise of commercial space flight agencies like Space X and Blue Origin, there’s more room for rich but not necessarily healthy people to go into space, so we want to use mathematical models to predict whether someone is fit to fly to Mars.”
There’s a scary thought – while Elon Musk certainly has enough money to build a ship to travel to Mars, does he look like he could survive the trip … let alone the first step onto the Martian surface? In a press release announcing the publication of their study, published in the journal npj Microgravity, co-author Dr Emma Tucker, an astrophysicist and emergency medicine registrar, warned that prolonged exposure to zero gravity can cause the heart to become lazy because it doesn’t have to work as hard to overcome gravity in order to pump blood around the body – a space variation of the inactivity problems we faced during the pandemic lockdown.
“When you’re on Earth, gravity is pulling fluid to the bottom half of our body, which is why some people find their legs begin to swell up toward the end of the day. But when you go into space that gravitational pull disappears, which means the fluid shifts to the top half of your body and that triggers a response that fools the body into thinking there’s too much fluid.”
We all know what happens when the body thinks you’re holding too much fluid … more trips to the bathroom, which is not an easy task in space. Furthermore, the brain is tricked into thinking the cause is drinking too much fluid, so it tells you to cut back, resulting in dehydration – a dangerous problem in space. After months in that condition, an astronaut’s body is no longer functioning the same as it was on Earth, but they don’t know it. Then the spaceship enters orbit around Mars and prepares for touchdown and deboarding. On Earth, astronauts already know what to expect, yet many still collapse or faint when they arrive. Fortunately, there is a support team there to help them revive and recover quickly. After years of orbiters and rovers searching for it, we can feel pretty confident is stating that there will be no welcoming team on Mars. Should the lander take the chance and bring the crew to the surface?
“The purpose of our model is to predict, with great accuracy, whether an astronaut can safely arrive on Mars without fainting. We believe it’s possible.”
That’s “possible.” The model had to take into account the fact that the distance between Mars and Earth causes a communication delay – any monitors in a spacesuit or cameras watching the first steps onto the Martian surface will need up to 20 minutes to send data and pictures of a collapsed astronaut to medical teams, whose instructions and actions won’t arrive back to the astronauts or equipment for 20 more minutes. That’s a lifetime to stop the possible end of a lifetime. Obviously, the Martian crews must be ready to treat their own emergencies upon landing and exiting the craft.
“This is why we must be absolutely certain the astronaut is fit to fly and can adapt to Mars’ gravitational field. They must be able to operate effectively and efficiently with minimal support during those crucial first few minutes.”
That’s “fit to fly” and smart enough to stay in shape both physically and mentally for seven months without getting bored and skipping their exercises in order to stream some movies from Earth. The ANU simulator used an algorithm based on astronaut data collected from past space expeditions, including the Apollo missions, to factor in all potential problems that could exacerbate the microgravity issues. It also modeled the bodies of middle-aged, well-trained astronauts. A certain previously-mentioned billionaire has been talking up sending everyday humans to colonize Mars, while other space billionaires are sending people in their 80s and 90s on short flights. The researchers say the next model will simulate impact of prolonged space travel on relatively unhealthy or older individuals with pre-existing medical issues like heart conditions to determine what will happen when an “everyday” person spends seven months is a small craft with nothing to do but stare at a screen, ride an exercise machine and loojk out the window.
Do we really need a simulator to tell us the Mars missions need to take loose-fit space suits, smelling salts and soft landing cushions?