Rocket launches are expensive.
Even with huge price drops from SpaceX and other New Space companies, there's no cheap
way to get stuff down here in Earth's gravity well up to low Earth orbit.
In order to really survive and thrive in space, we've got to learn to live off the land,
to acquire the resources in space that will allow us to survive… in space.
We've got to learn to turn those raw materials into forms we need: fuel, breathable air,
water, construction materials, and eventually even finished goods like rocket parts and
electronics.
The Solar System really has everything we need to be able survive in space for the long
term.
Every single element we have on Earth is out there in space.
There are deposits of water ice across the Solar System, from the permanently shadowed
craters on the Moon to the comets and dwarf planets in the Kuiper Belt.
The planets and even asteroids and comets have the metals and other minerals we'll
need for our manufacturing.
To top it all off, of course, the Sun is blasting solar radiation across the Solar System, and
it's just there for the taking, before it's lost into deep space.
In the past, space missions carried everything they needed from the Earth to space.
All the air, water and food the astronauts would need, as well as the propellant for
their rockets.
But you need to carry all that mass up, out of Earth's gravity well.
A Falcon 9 will cost you almost $5,000 per kilogram, and even a Falcon Heavy will still
be $1,700/kg.
To send a kilogram to the Moon will probably cost you $50,000 to $100,000 per kilogram.
Too much I say!
As part of their space exploration plans, NASA, ESA and other private and public space
entities are working out techniques and technologies to harvest the resources we need from the
Solar System itself.
This technology is called In-Situ Resource Utilization, or ISRU.
In December 2017, NASA released a request for proposals from aerospace companies to
fulfill its In Situ Resource plans, and they encouraged companies to suggest ideas for
prospecting, resource acquisition, processing, manufacturing, construction and finally energy
collection.
I wanted to take you through each of these concepts, and let you know about some of the
ideas and missions in the works that will try to make it happen.
All right, first up, prospecting.
In other words, scanning the Solar System in search of the kinds of resources we're
going to need to survive.
We know there's water out there, but how much?
Where's it concentrated?
Is it sitting on the surface or embedded in the regolith?
The Korean Aerospace Research Institute is building a mission to the Moon called the
Korea Pathfinder Lunar Orbiter or KPLO.
This spacecraft is expected to fly to the Moon in 2020.
It'll have a suite of instruments on board, but one of the most interesting is called
ShadowCam, which is being supplied by NASA.
This will have the ability to peer into the permanently shadowed craters near the poles
on the Moon and search for water ice which could have survived for billions of years.
If these deposits are there, they'll be able to provide astronauts with an enormous
amount of water ice, right on the surface of the Moon.
There are asteroids out there that'll have more precious metals in them, like platinum,
than the total that's ever been mined here on Earth.
Which asteroids contain the mother lode, and which are just piles of rock?
There are two companies which are building up the infrastructure to help us find out.
The first is called Planetary Resources, and they've already launched their Arkyd-6 satellite
earlier this year.
This cubesat is a demonstration of the kind of technology they plan to use to search the
Solar System for resources.
If all goes well, they'll launch several Arkyd-301 satellites in 2020, which will launch
to different asteroids.
Each one will study the space rock's resource potential, and even deploy miniprobes to get
an even closer look.
Another company working on this is Deep Space Industries, with their Xplorer satellite which
they're hoping to launch in 2020.
This spacecraft will be capable of boosting itself out of low Earth orbit, rendezvousing
with a target like an asteroid or comet.
One of the clever features of the Xplorer is their Comet water-based propulsion system.
The rocket superheats up water and then accelerates it out the back.
It won't happen yet, but imagine a time when one of these spacecraft could refill
its water propellant tanks from a comet or asteroid and then blast off to a new target.
I can imagine a future when the Solar System is buzzing with these little probes, scanning
and sending back data to Earth so we'll know exactly where to send the next class
of spacecraft: resource acquisition.
Resource acquisition involves excavation into the regolith of other worlds, drilling into
the ice, and collecting gases from the atmosphere.
About 10 years ago, NASA held the Regolith Excavation Challenge.
This was a race for where various teams would build an autonomous robot that would dig material
out of a simulated regolith.
The winning robot needed to be able to dig up and deposit at least 150 kilograms of simulated
lunar material into a collection bin within 30 minutes.
In the first two years of the challenge, nobody won, and then in the 3rd year, a team from
the Worchester Polytechnic Institute was able to collect more than 500 kilograms within
the time limit.
Next up is resource processing, providing resources that could be used right away, like
propellants, building materials or water for drinking.
One mission that's in construction right now that'll test the feasibility of making
rocket fuel on another world is the Mars 2020 rover.
Although this twin to Curiosity is a mobile astrobiology lab, it's also equipped with
the Mars Oxygen In-Situ Resource Utilization Experiment, or MOXIE.
The purpose of this experiment is to break down the carbon dioxide atmosphere on Mars
to produce oxygen.
If all goes well, it'll be able to generate 22 grams of oxygen every hour over the course
of 50 Martian days.
If this technology works out, NASA thinks they can land an oxygen plant that's 100
times more powerful, and could fill up a fuel tank that a human Mars mission would use to
return to Earth.
Manufacturing.
Creating replacement parts, machines, and various systems out of the raw materials acquired
from space.
One of the biggest challenges to living in space will be the need for manufacturing,
creating the replacement parts, machiness and various systems out of the raw materials
we find in space.
It's not like you can just go down to the computer store to replace the motherboard
for your guidance computer.
NASA has been investing efforts into 3D, or additive manufacturing methods to learn how
to construction objects out of raw materials in the microgravity of space.
There's a 3D printer on the International Space Station right now called the Additive
Manufacturing Facility, it was developed by a company called Made in Space, which is actually
working on a range of techniques and technologies to manufacture objects beyond the Earth.
The AMF is about twice the size of a traditional 3D printer, and can manufacture complex objects
using a range of aerospace grade materials.
So far it's built custom wrenches and other tools, artwork, sample collection containers
and more.
But Made in Space has won a contract with NASA for an even more ambitious mission called
Archinaut which is a 3D printer crossed with a satellite that could manufacture larger
structures in space, like telescopes or space station modules.
It would have a 3D printer on board to manufacture parts in the vacuum of space, and then 3 arms
to assemble and attach the parts together.
Building these structures in space has a huge advantage.
Keep in mind, not only do spacecraft launched from Earth need to be able to handle being
in space, they need to survive Earth first, and then the punishing launch to space.
Instead of launching a fragile next generation telescope into space, and then hoping it unfolds
and deploys properly, NASA would launch the Archinaut with appropriate building materials.
It would then use solar power to manufacture the structures of a huge space telescope to
an extremely fine resolution.
Then it would assemble them together.
Only the parts that absolutely needed to be built on Earth would need to be launched to
space.
If all goes well, we could see a test mission for Archinaut launching in the mid-2020s.
NASA actually makes a range of objects available for download from its website, so you can
3D print your own asteroid, or OSIRIS-REx spacecraft.
We've talked about some of NASA's ISRU plans already, but next we're going to talk
about space construction and harvesting energy.
But first I'd like to thank:
Zachary Makowski Tim Allen
Charles Kahle Diego Colonnello
Jon Corrigan
And the rest of our 831 patrons for their generous support.
If you love what we're doing and want to get in on the action, head over to patreon.com/universetoday.
Let's move onto construction, building large structures like habitats, roads, radiation
shields and landing pads on other worlds.
The European Space Agency has been testing out a technique where regolith on the Moon
- the volcanic rock pulverized by micrometeorite impacts - could be turned into building materials.
By using a 3D printer, they were able to create walls with hollows inside them, similar to
bird bones, which provide the maximum amount of strength for the minimum of weight.
The 3D printer consists of a frame 6-meters across with an array of nozzles.
Lunar regolith is mixed with magnesium oxide and then blended with a binding agent.
It's then sprayed onto a sandy building material, one layer at a time.
Their current prototype builds at a rate of 2 meters per hour and could eventually create
a new building every week.
You can imagine this same technology being used to create roads across the surface of
the Moon or Mars landing pads, and more.
NASA has a similar technology in the works called Contour Crafting, which blends together
regolith and magnesium oxide together and then extrudes it out into various shapes.
It could build interlocking tiles and bricks.
And a new technique called Selective Separation Sintering recently one first place in a NASA
In-Situ Materials Challenge.
This technique can work in zero gravity, which means that material from the Moon or asteroids
could be brought into space and then manufactured into various useful structures.
Last but not least, let's talk about energy.
We just did an episode all about space energy, but there are a few interesting ideas to concentrate
the Sun's rays for use farther out into the Solar System.
Space provides energy in the form of radiation from the Sun.
Here at Earth, there's about 1,360 watts of energy from the Sun falling on every square
meter of space.
At Mars it's about 715 watts.
And once you get out to Jupiter, it falls to about 50 watts per square meter.
You can use solar panels close to the Sun, but if you're farther out, you can use solar
concentrator arrays to focus the sunlight onto a smaller solar panel.
One spacecraft to use this technology was NASA's Deep Space 1 spacecraft, which also
demonstrated several other novel spaceflight technologies.
Its array used 720 lenses to focus sunlight onto 3600 solar cells giving it about 2,500
watts when it was in Earth orbit.
You can also use reflective mirrors to concentrate the Sun's rays.
When do you go with solar panels and when do you use a concentrator?
According to a paper from Travis Deyle, as you make solar panels and concentrators bigger,
there's an overlap point where the concentrator scales up cheaper than the panels.
NASA has actually developed a series of inflatable space-based membrane concentration systems
and tested them in vacuum chambers.
To acquire resources from Mars, the asteroid belt and beyond, you're going to need a
lot of energy, and these inflatable solar concentrators might be your best way to get
it.
I know this is already a pretty long video, but I'm actually just scratching the surface
here.
There are dozens, even hundreds more really interesting ideas proposed for in-situ resource
utilization, so I just provided a few highlights.
As new projects are developed, I'm sure I'll come back to this topic again and again.
Once we set our robots loose in the Solar System, extracting raw materials from asteroids,
comets and moons, and then turning it into bases, observatories, and rocket fuel, we'll
have a real shot at becoming a true Solar System spanning civilization.
What do you think?
Do you have any ideas for living off the land in space?
Let me know your thoughts in the comments.
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