rivers and lakes. Even its day is 24 hours...and 37 minutes. But with everyone talking about

manned missions to mars, could we actually successfully colonize the red planet with

humans?

Let’s start with the good news: there’s plenty of water. It’s been estimated that

there are more than 5 million cubic kilometres of water frozen into ice caps at the northern

and southern poles. Melt all this down and there would be enough to cover the planet

in an ocean 35 metres deep.

And this water could help solve a second problem: finding something to breathe. Mars’s atmosphere

is very thin and made almost entirely of carbon dioxide, not the oxygen us humans have adapted

to breathe. But, colonists could use electricity to split the H20 in hydrogen and oxygen. Take

that oxygen and pump it into air-tight living structures, and now you’ve got somewhere

to party!

Of course, food would be another barrier. Shipping animals to Mars would be...eh, complicated,

so colonists would need to start out as vegetarians. And since plants need sunlight, the fact that

Mars is about 1.5 times as far from the sun as Earth is, means they would only receive

about half the average solar irradiance. But scientists have actually experimented with

this; in fact, there is a Mars simulation colony in Devon Island, way up in Northern

Canada which receives an equivalent solar radiation as Mars. And it’s been confirmed

that there would not only be enough light to sustain plants on Mars, but that things

like tomatoes, carrots and other crops could grow in simulated Martian soil.

Of course, growing enough food could actually create so much extra oxygen that it would

become a fire hazard. To counteract this, oxygen would have to be diluted with non-reactive

gas like nitrogen, which Mars has very little of. But bringing it from home would only add

to the cost of the trip.

Speaking of bringing things from home, it’s inevitable that at some point a machine or

system would break down and require a replacement part. The shortest distance from Earth to

mars is 55 million km, but at times the two planets are on opposite sides of the sun.

So, for practical reasons, spacecraft can only be sent to Mars every 26 months. Considering

the International Space Station, our longest standing experiment with living in space,

needs to be re-supplied every 90 days or so, 2 years and 2 months wait time may be pushing

it. Add to that the cost of launching equipment into space, which is around $10,000 per pound,

and delivering spare parts becomes a major challenge.

Finally, there are threats to human health. Mars is smaller than Earth, and its gravity

is only ⅓ what we’re used to, which is awesome for jumping high and creating structures

of lighter materials, but not so great for our bodies. We depend on the constant pressure

of gravity to build up our bones and muscles; in fact, astronauts must undergo regular exercise

in space to keep themselves in shape.

But even worse is the cosmic radiation. The sun spews out billions of high-energy particles

that can damage our DNA and cause cancer. Luckily, Earth has a powerful magnetic field

that deflects 99.9% of these particles, but Mars has no magnetic field, meaning travellers

would be completely unprotected on their journey. On the shortest possible trip, this would

raise an individual's risk of developing cancer by more than 3 percent.

Theoretically, none of these problems are completely insurmountable. Perhaps supermagnets

could be created to ward off radiation, advanced propulsion systems could reduce the time it

takes to get to Mars, and we might even develop next-generation 3D printers that could produce

spare parts on site from Martian materials. But all of this will require significant advances

in technology beyond what we have now. That being said, it is possible that the people

who will create this technology have already been born. Maybe it’s you...will you become

a martian?

Special thanks to Audible.com for supporting this episode and giving you a free audio book

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over 150,000 downloadable titles across all types of literature. We recommend the book

“Packing For Mars” which is a hilarious explanation of everything it takes to venture

into space! You can download this audio book or another of your choice, for free, at audible.com/asap.

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