Jordi Pereyra: "We already have the technology to colonize a planet in the Solar System"

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Jordi Pereira

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Ibiza, 1990. Graduated in Mechanical Engineering and science communicator, author of the blog

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In

(Paidós) he explains how not to die on a distant planet if you only have some rocks (and some basic notions of chemistry).

Let us imagine, as you suggest in your book, an astronaut whose ship is stranded on an inhospitable and distant planet, without water, oxygen, or food.

What can you do?

If you are on a completely hostile planet, where there is no water or living beings or anything, only rocks and dust as far as your eyes can see, you can survive with those rocks.

But you can't eat or drink or breathe rocks, right?

But things can be extracted from rocks, because in the end everything that surrounds us, the rocks themselves, are made of different chemical elements.

What happens is that these chemical elements are not in the state in which one would like, they must be transformed through chemical and mechanical techniques into substances that can be used and consumed, be it water, oxygen or fertilizers.

It is, in fact,

of methods we have used since time immemorial on Earth to survive on our own planet.

In space, is there water?

Yes, water abounds in the universe, what happens is that it is not usually in a liquid state and that is the problem.

Two of the most abundant elements in the universe are hydrogen and oxygen.

Water is made up of H2O molecules, which means that each water molecule is made up of two hydrogen atoms and one oxygen atom.

And what state is it usually in?

In the form of vapor or directly in the form of ice.

On almost every planet in the solar system, and even on the dwarf planets in the outer reaches of the solar system, there are large amounts of water in the form of ice.

In most of the surface of the Moon it is difficult for there to be water because the temperature of the lunar surface reaches 120 degrees when the sun hits it, but there are some craters at the poles that are permanently shadowed, they never get the sun, and there are indeed large reserves of ice.

A good place for a mission, for a settlement, would be the poles of the Moon, where there are very large water deposits.

In fact, one of the reasons why it has been proposed to set up lunar bases is that water can be taken there, broken down into hydrogen and oxygen through a process called electrolysis, and the hydrogen and oxygen that are extracted from the water would serve as fuel to propel ships.

The Moon is considered above all as a kind of bridge, a ferry, which allows launching to the rest of the solar system,

because launching things from the Moon is much easier.

Since the Moon has a weaker gravitational field than Earth's and has no atmosphere, it is easier to launch ships from there.

And you can also draw water from the rocks.

And are there rocks in space from which water can be extracted?

Gypsum, for example, is made from hydrated calcium sulfate, which means that it is made from calcium sulfate, which is a salt, and hydrated: which has water molecules in its chemical structure.

If you heat the plaster, the water escapes as a vapor and you can capture it and turn it into a liquid.

And if it's pure enough, even drink it.

I have done the experiment and I have a video posted on the YouTube channel in which I extracted water from the plaster.

I didn't drink it because it smelled like gunpowder, and I had it tested and it wasn't exactly drinkable.

But if you are an astronaut trapped in another Solar System you will surely have more sophisticated equipment than I had and you will be able to purify it until you can drink it.

On the International Space Station I understand that urine is recycled, right?

Yes. Recycling and reusing resources is basic to any space mission.

If you don't have the necessary resources to survive in your environment and they can't be sent to you from Earth, because it's too expensive and it's too far away, you have to recycle what you have on hand.

And one of those things is urine.

On the International Space Station, urine, sweat, and accumulated moisture are collected, filtered, processed, and purified to provide water for astronauts.

This saves a lot of money and space,

of cargo capacity of the ship that can be used for other things.

We already have water.

But where do we get the oxygen we need to breathe?

The good thing about water is that, being made of hydrogen and oxygen, it is also a source of oxygen.

By electrolyzing water, oxygen can be obtained.

If there is no water available to you on that other planet, then you will be forced to take more drastic measures, to use more inefficient methods of getting oxygen, such as getting it from rocks directly.

Many rocks that surround us, and those that make up other planets, contain large amounts of oxygen in the form of oxides, silicates... If the rocks melt, something that requires a lot of energy because it takes a thousand and something degrees to do it, and a very strong electrical current passes through this molten rock,

you can separate the oxygen from the rocks, which escapes in the form of gas and so you could breathe it.

The problem is that it is a very inefficient and quite dangerous method, of course it is an experiment that no one should try to do at home.

And if there are any space castaways reading this paper I would recommend that if you have a water source handy or any other much easier way to get oxygen, that you use it instead of melting down rocks.

We already have water and oxygen.

But what do we eat?

To eat in space, there is no other option but to bring some type of plant from Earth.

You need your space base to have a greenhouse and most likely also bio-reactors, tanks in which to grow algae, edible bacteria... In fact, on Earth this type of thing is sometimes eaten, an example is spirulina.

This type of microorganism is very useful for space missions, because it is a very efficient way of obtaining edible material.

In addition, they need very few resources to grow and do not take up much space.

But those plants and those bacteria will also need to feed on something to survive, right?

Yes. That's where fertilizers come into play.

On Earth we have sometimes used fertilizers from a bit odd sources.

In the 19th century in the UK, for example, they used fossil feces to fertilize crops.

And I also found a document that speaks of a shipment of mummies that were also taken from Egypt to the United Kingdom in the 19th century to crush them and spread them in the fields as fertilizer.

When you do not have a source of fertilizer at hand, you try to get it from where you can,

and there was a time when human beings had to use imagination.

The most important fertilizers in our environment are, above all, rocks rich in potassium and nitrogen, and this type of rock is present on other planets.

In the book I explain how they can be identified and how to process them into substances that plants can use to grow.

Sometimes lightning, when it strikes the right ground, can transform minerals into what are called fulgurites, hollow tubes made of semi-molten material.

If we were stuck on a planet with a lot of electrical activity in terms of storms, these fulgurites could potentially be used to produce fertilizer.

But on other planets where there is no electrical activity,

that chemical process that takes place when lightning strikes the ground you will have to do on your own.

And the energy?

Where would it be obtained on that inhospitable planet?

For a long time on Earth we have obtained energy by burning fossil fuels, most of which come from the decomposition of organic matter, matter that has been alive at some point.

It may happen that certain fossil fuels are formed abiotically, that is, without the need for the remains of living organisms, but it is rare.

So most of the space castaways won't be able to rely on fossil fuels because most of the planets have surely been lifeless.

Then?

Then they will have to stretch their imaginations again, either by using "renewable sources" such as wind power as much as possible.

Although there are celestial bodies that do not have an atmosphere and windmills cannot be installed there because nothing would move them, and planets so far from their star that they do not receive enough light to produce energy with solar panels.

If the planet you're stuck on is very, very old, the radioactive elements it contains will have decayed and you won't be able to get fissile uranium to produce nuclear power either.

It depends a lot on the type of planet you are on, there are many options but they have to be available in your environment so that you can use them.

But I assume that the space castaways have an interplanetary base minimally equipped with a nuclear pile, as do the unmanned missions that go very far,

and that therefore they have a margin of several decades to find some way to produce energy in their environment.

And is it possible to build something resembling a home on that bleak planet?

By power, you can.

The problem is that unless you end up trapped on a planet quite similar to Earth - that is, with liquid water, with a dense atmosphere, etc. - you will be forced to live a bit like we did here in confinement, to make life in interiors.

It has been proposed to make bases on the Moon or Mars, but the Moon does not have an atmosphere, and that means that on the lunar surface you are much more exposed to radiation and micrometeorites that do not stop bombarding it.

On Mars, the atmosphere is very thin, so the dangers you would be exposed to on the surface would be similar.

That means that both on the Moon and on Mars you will have to leave your base as little as possible to avoid being exposed to that radiation and the danger posed by micrometeorites.

In many celestial bodies and if in the future we get to settle in them, we will have to lead a fairly interior life, because the exterior will be too hostile for human life.

As much as things go wrong on Earth, it will always be better here than on another planet.

At least for now.

Today, would it be possible to organize a mission to try to colonize a planet?

Within our Solar System, in principle we already have the technology to do so.

In fact, missions are beginning to be considered for settlements both on the Moon and on Mars.

There are no dates yet, but it is something that can be done with current technology.

It costs a lot of money, but it can be done.

What is totally out of our reach right now is to do it in other solar systems, because the distances are too great.

Guide to survive in space

(Paidós), by Jordi Pereyra, is already on sale.

you can buy it here

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