By popular request, Isaac Arthur and I have teamed up again to bring you a vision of the
future of human space exploration.
This time, we bring you practical construction tips from a pair of Type 2 Civilization engineers.
To make this collaboration even better, we’ve teamed up with two artists, Kevin Gill and
Sergio Botero.
They’re going to help create some special art, just for this episode, to help show what
some of these megaprojects might look like.
I’d also like to congratulate Gannon Huiting for suggesting the topic for this collaboration.
We both asked our Patreon communities to brainstorm ideas, and his core idea sparked the idea
for the episode.
You get one of my precious metal meteorites, which I guarantee will give you a mostly worthless
superpower.
We’ll tell you the story of what it took to go from our first tentative steps into
space to the vast Solar System spanning civilization we have today.
How did we extract energy and resources from the Moon, planets and even gas giants of the
Solar System?
How did we shift around and dismantle the worlds to provide the raw resources of our
civilization?
Humanity’s ability to colonize the Solar System was unleashed when we harvested deposits
of helium 3 from the Moon.
This isotope of helium is rare on Earth, but the constant solar wind from the Sun has deposited
a layer across the Moon, though its regolith.
Helium 3 was the best, first energy source we got our hands on, and it changed everything.
Although other kinds of fusion reactors can produce more energy with more efficiency,
the advantage of helium 3 is that the fusion reaction releases no neutrons.
This means you can have a fusion reactor on your starship or on your base with much less
shielding.
We still use helium-3 reactors when living creatures need to be close the reactor, or
the ship can’t afford to carry around heavy shielding.
The Helium 3 is found within the first 100 cm of the lunar regolith.
Harvesting it started slowly, but in time, our mining machines grew larger, and we stripped
this layer completely off the Moon.
There are other repositories across the Solar System, in the regolith of Mercury, other
moons and asteroids across the Solar System, and in the atmospheres of the giant planets.
We later switched to getting our Helium 3 from Uranus and Neptune, but the Moon got
everything started.
One of our big problems with building in space was getting raw materials.
Just about every place that has the supplies we needed was at the bottom very deep gravity
wells which made accessing those materials a lot harder.
Asteroid and moons offered us a large supply of material that was not locked inside such
deep gravity wells.
These asteroids also gave us a big initial head start on developing space-based infrastructure
as they contained a great deal of precious metals that we could bring home to help fund
our endeavors.
For all that, the entire Asteroid Belt contains much less material than Earth’s own Moon.
The ease of mining and transport on these bodies made them a critical source of raw
materials for building up the early Solar Infrastructure and many of them became homes
to rotating habitats buried deep inside the asteroid, where millions of people live comfortably
shielded from the hazards of space and support themselves mining the asteroid around them.
These asteroids and moons often contained water in the form of ice, which is vital to
creating life-bearing habitats in space, as well as fuel and propellant for many early-era
spaceships.
However, even if the entire Asteroid Belt was ice, instead of it being a fairly smaller
percent of the mass, that would still only be the approximate mass of Earth’s Oceans.
There was a plentiful supply for early efforts but not enough for major terraforming efforts
on places like Mars or creating many artificial habitats.
Water is incredibly scarce in the inner Solar System, but becomes more plentiful as we make
our way further out, past the Solar System’s Frost Line.
Deeper out past the planets we find enough water to make whole planets out of, as hydrogen
and oxygen are the first and third most abundant elements in the Universe.
Also, for the most part these come in convenient iceberg-sized packages, low enough in mass
to have a small gravity well and to be movable.
Mastering the Solar System required moving very large objects in space.
For the less massive objects, we could put a big thruster on it, but for the largest
projects, such as moving planets with atmospheres, (which we’ll get to in part two), another
technique was required.
To move large objects around, without touching them, you need a Gravity Tractor.
Want to move an asteroid?
Use the gravity of a less massive object, like a spaceship.
Hold the spaceship close to the asteroid, and their gravity will put them together.
Fire your rocket’s thrusters to keep the distance, and you slowly pull the asteroid
in any direction you like.
It takes a long time, and does require fuel, but you can use this technique to move anything
anywhere in the Solar System.
Put a massive satellite into orbit around an asteroid.
When the satellite is on one side of the asteroid it fires its thrusters towards the satellite.
And then on the other side of its orbit, it fires its thrusters away from the satellite.
The satellite will have been pushed twice in the same direction.
To an outside observer that satellite has moved, though on the asteroid it will seem
to have been nudged closer than put back.
Don’t forget that the satellite pulls on the asteroid with just as much force as the
asteroid exerts on the satellite.
Earth pulls on the Sun just as hard as it pulls on us, but it’s more massive so it
doesn’t move as much.
But it does move, and so by pushing on the satellite towards the primary then pushing
away on the opposite side, we move the primary body.
We can also take advantage of momentum transfers from gravity to alter the course of an object
by making a close flyby.
You can use this gravitational slingshot to use the gravity of a planet to change the
move large objects into a new trajectory.
Over time, we put gravitational tugs into orbit around every chunk of rock and ice that
we wanted to move, shifting their locations to the best places in the Solar System.
Some places gave us raw materials.
Other places would serve as our homes.
Earth is the third closest planet to the Sun and it will always be the environment we’re
trying to replicate.
Earth is, well, it was... home.
For all the millions of other worlds across the Solar System, we made them capable of
hosting life with a little work.
Often we could make them habitable just by increasing the amount of energy they received
from the Sun.
Creating artificial gravity by spinning a habitat or breathable air by doming it over
did us no good if there wasn’t enough light to melt ice into water or let plants grow.
The farther you get from the Sun, the less light you get, but we bounce light that would
have been lost, concentrating it to let life flourish.
The Sun gives off over a billion times the light that actually reaches Earth, so there’s
no shortage in quantity, just concentration.
To double the light reaching a planet like Mars, you would need a mirror surface area
of twice the size of Mars.
But not twice the mass of Mars.
For every square meter of land on Earth, there’s about 10 billion kilograms of mass under our
feet.
A mirror on Earth wouldn’t weigh much more than a kilogram a square meter, but in space
we can go far thinner.
Any one of millions of small asteroids in the solar system contains enough material
to make a planetary surface’s worth of mirrors.
Lenses or parabolic reflectors let us move light in from far more densely concentrated
locations closer to the Sun.
Reflecting light also allows us to remove harmful or less useful invisible wavelengths
like ultraviolet or x-rays.
This allowed us to make almost any place warm and bright enough.
We took distant moons and asteroids far from the Sun, and gave them a collar of thin mirrors
bouncing light into a parabolic dish.
By bouncing this light into rotating habitats safely buried inside the asteroid, we created
warm, lush garden worlds in environments so cold that air itself would condense into a
liquid.
For most of the Solar System we wanted to warm planets up.
But for Venus and Mercury, we needed to cool them down.
We did this by placing shades between them and the Sun to reflect away some of the light
hitting them.
The easiest way to do this was to position an opaque material between the planet and
the Sun, at the L1 Lagrange point.
At this point the gravitational pull of the planet counteracts the pull of the Sun allowing
a large thin solar shade to remain in position with minimal energy.
This way the planet is cooled.
But we did better than merely cool, we shaped the light to our needs.
With a collection of many small shades, we avoided putting a visible dark spot on the
Sun.
Sunlight comes in many frequencies, from radio to x-rays; some were more valuable to us than
others.
Plants mostly use red and blue light, while green light doesn’t help with photosynthesis.
So blocked a decent amount of green light, some blue, and no red, and cooled the planet
without harming plant life and without really altering how the light looked to our eyes.
We engineered the perfect material for our shades which was mostly transparent to the
wavelengths of light we wanted and mostly reflective or absorptive to the ones we didn’t.
Ultraviolet is a good example.
We wanted some to get to our planet, as it does help as a sterilizing agent to biological
processes and it helps make ozone, but we wanted to cut most of that out.
Even better, about half of the light coming from the Sun is in infrared, which we can’t
see and which plants don’t use.
We blocked most of that and seriously lowered temperatures on Venus and Mercury.
Enjoying this epic adventure into the future of humanity?
Good news, our journey continues over at Isaac Arthur’s channel.
In that episode, we create artificial magnetospheres, shift the planets around, and eventually dismantle
them to build our vast, Solar System-spanning Dyson swarm.
The great achievement of a Type II Civilization.
Click here to see Part 2.