The theoretical road to Mars

The theoretical road to Mars

Tarik Haiga considers the scientific and mental challenges on our way to the Red Planet

On November 8th 2016, Donald Trump became the next president-elect of the US. Maybe you’re thinking about leaving home? Or maybe to somewhere else farther, like Mars? Apparently, this kind of journey has received a lot more interest since Election Day.

But travelling to outer space has never been easy, let alone travelling over 54.6 million kilometres (the distance varies due to the two planets’ different orbits). While advanced technology is one part of the solution to a successful journey to Mars, the mental health and well-being of the spaceship’s crew are a critical factor that a lot of people fail to consider.

Scientific challenges

The first step in the journey to Mars is to escape Earth’s gravity and get into outer space. To do so, the spacecraft’s speed needs to be around 11 kilometres per second, or 40,000 km/h. This creates a host of its own challenges: the heavier the spacecraft, the slower it travels. And because astronauts will need to take everything they need to survive with them, several trips from Earth to outer space would be needed to transfer food, equipment, and the most important (and dangerous) material that is going to be carried, fuel, which is highly susceptible to vaporization, explosion and leakage.

Once those problems are solved, the scientists and engineers canstart to think about the next ones. In space, there are a lot of moving objects; space debris, for example, or junk. If birds can damage a commercial aeroplane, objects travelling at speeds that exceed 28,000 km/h can cause a catastrophe.

Revisiting the challenge of the spacecraft’s speed, there is also the difficulty of the craft staying in the right trajectory around Mars when the planet itself is orbiting around the sun. In addition, the transmission of information between Earth and Mars will be very slow and probably unreliable, putting the mission at risk as well as negatively influencing the crew’s mental health.

Then there’s landing. Entering the martian orbit will happen at speeds that exceed 19,300 km/h, and the first step to slow down will be the friction between craft and atmosphere. Next, a parachute will be opened to further decrease speed, followed by retro-propulsion (firing engines against the direction of travel) that will reduce the craft’s velocity to subsonic levels. Then it falls, freely, from the height of a 4-story building, and hits the ground  at a speed of 48 km/h (or up to 80 km/h in the presence of winds) whilst airbags are deployed to cushion against the crash.

The negative effects on the human body of being in space include radiation, bone damage and muscle loss. Here on Earth, we are shielded from cosmic rays thanks to our planet’s atmosphere and magnetic field. In space, where ionizing and carcinogenic radiation abound, spacesuits and the spacecraft itself would have to be built from materials that dramatically reduce radiation exposure to avoid proliferation of diseases like cancer. Speaking of disease, when astronauts don’t use their bodies as they’d use them on Earth (due to the lack of gravity), they experience muscle atrophy and decreased bone density. And these are just a few of the physical problems that astronauts travelling to Mars would have to overcome.

Psychological challenges

Astronauts have to accustom themselves to something we don’t usually experience in today’s world: isolation.

The farther we travel in space, the harder it is to maintain a real-time connection with those we care about. This can trigger depression, mood swings and emotional instability. Not only that, but in cases of danger or emergency, astronauts have to be self-reliant, dealing with their troubles themselves.

The relationships between astronauts themselves can be a hurdle too. Misunderstandings are bound to happen, but serious disagreements between individuals will be harmful for them and for the mission. Therefore, astronauts need to know how to strike the right balance between their private time where, for instance, they can work individually on problems, and social time, during which they can get together for work or leisure.

To be confined to the spacecraft and their spacesuits can increase astronauts’ feelings of isolation, anxiety and boredom. Gone is the individual’s ability to freely move from one place to another, something we take for granted on Earth. And because of this, astronauts will have to deal with a profound lack of privacy, as they will be monitored by the rest of the team on Earth.

If we take into account the psychological obstacles that astronauts have to go through – not only the ones that stem purely from social interaction, but also from their diet, physical condition, and workload – we can understand how rigorous and selective the process of being chosen to embark on such a journey must need to be.

There have already been experiments to test the ability of human beings to live in isolation. Participants who lived for two years in Biosphere 2, a closed complex in the Arizona desert that simulates the Martian environment, said that isolation was the hardest part. Some of them developed mental illnesses and sought the help of psychologists. But once you’re on your way to Mars, there’s no going back for a counselling session; this way of life could cause even the most prepared of people great distress. Scott Kelly, the American former astronaut who spent almost a year on the International Space Station, was very glad to return: “Having spent a year on the space station, I can’t imagine spending the rest of my life in an environment like that, where you can’t go out and get fresh air.”

We may all think that an atmosphere with 96% carbon dioxide would be a breath of fresh air compared to living under Trumps presidency, but it’s time we respected the sacrifices and risks astronauts make in order to undertake space explorations. Not to mention the astonishing physics of space travel. Given the option, would you be willing to travel to the red planet?

Image Credit: Wikimedia Commons

Tarik Haiga