This is Mark Watney.

He’s an astronaut who’s been living on Mars for just over a year – an Earth year.

Watney didn’t intend to stay on Mars for that long.

He was part of the Ares 3 mission, which was hit by a violent storm soon after landing.

The rest of the crew evacuated, and Watney was left behind.

This is the story of The Martian, a film based on Andy Weir’s 2011 novel.

The novel and film are pretty scientifically accurate.

Living on the red planet isn’t easy, and Watney does a amazing job of surviving on

Mars, despite the odds.

The atmosphere on Mars is 95% carbon dioxide and is about 80 times thinner than Earth’s

atmosphere.

It’s as good as a vacuum to your vitals.

If you were exposed to the atmosphere, your saliva, tears, skin moisture and the water

in the alveoli of your lungs would boil away.

That’s right Physics Girl.

So Watney lives in a pressurised environment with an oxygenator and atmospheric regulator.

But even with this equipment, there’s still a lot of weird things that can happen to you

if you live on Mars, or elsewhere in space.

During the Apollo 11 mission in 1969, Buzz Aldrin reported seeing strange flashes of

light.

Later experiments found the high-energy charged particles that make up cosmic rays were causing

astronauts, just like Buzz, to perceive these flashes.

Cosmic rays are a form of radiation, typically very high-energy and often composed of protons.

Some originate from our sun, some from outside our solar system, possibly from the supernovae

of massive stars.

These light flashes perceived by astronauts are called Cosmic ray visual phenomena.

The thing is, the light flashes aren’t real.

You can’t see cosmic rays.

The cosmic rays pass through the astronaut’s eyes, mess with their optic nerve and make

them think they are seeing flashes of light.

And studies have found that astronauts often have poorer vision after space flight.

Increased pressure and fluid shifts in their heads can cause structural changes in the

eye.

On Earth our magnetic field protects us against radiation from cosmic rays.

It protects astronauts on the International Space Station too, they’re only about 400

km away.

But on further missions, like ones to Mars, cosmic rays mess with more than your vision.

In one study, researchers exposed mice to small doses of the kind of radiation people

would experience on a nine month trip to Mars.

You know, cosmic rays.

Typically very high-energy and often composed of protons.

After 6 weeks, the researchers noticed changes in the structure of the mice’s brain cells.

They had fewer dendrites, the little branches that carry electrical pulses of information

from cell to cell.

The mice became confused more easily and were less likely to explore.

The researchers suggested if this happened in astronauts, it could impair their ability

to problem solve.

Tests have also shown astronauts can lose 1% of their bone density per month in space,

compared with the 1% we lose a year on earth.

They have disturbances in their sleep, balance and blood pressure which all adds up to be

pretty stressful.

Astronauts are incredibly brave and despite all this, they go into space all the time

and many live very long lives.

But we’ve only been as far away as the Moon.

What would happen if people travelled to, say, Mars?

There’s lot of interest in going, from NASA’s Orion spacecraft to SpaceX’s Mars Colonial

Transporter, but remember that Mark Watney, unfortunately, is a fictional character.

We haven’t been there yet, and we don’t know what it might do to our brains - psychologically

or physiologically.

According to NASA, a manned mission to Mars would take roughly nine months to get there,

and nine months to get back.

And the astronauts would have to stay on Mars for three months before Earth and Mars realign

for a return trip.

So we’re looking at a 21 month mission.

We have started preparing for a manned Mars mission.

Mars500 was an isolation experiment that ran for 520 days in a pressurised facility in

Russia.

From 2007 to 2011, three crews lived and worked in a mock spacecraft.

Mars500 was the longest simulated space mission, ever.

As missions increase in distance and duration, there’s a constant dependence on automated

life-support systems, a higher degree of isolation and confinement and the lack of short-term

rescue possibilities in case of emergencies.

The astronauts on this mission did a lot of psychological evaluations before the mission,

during and after.

The European Space Agency described the most useful personality traits for an astronaut

as tolerance, sympathy, balance in time spent in a group and alone, and a sense of humour.

And these are some traits looked for in astronaut selection.

NASA psychologists add that good astronaut candidates are easygoing, have good social

skills and are also very resilient.

Going back to The Martian, we can see these traits in Mark Watney.

His resilience, easy going nature and sense of humour all contribute to his story.

And we can see these traits in astronauts in real life space dramas.

Like when Apollo 13’s oxygen tank exploded or when astronauts had to fix Hubble’s faulty

mirror.

There is some exhilarating science behind these two space “rescues”.

Follow me over to Physics Girl where Dianna explores the most epic space rescues

in history.

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