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Quietly on January 1, 2009, a company
called Arkyd Astronautics was formed,
a secretive organization with a cryptic name
and with ties to billionaires like XPRIZE founder Peter
Diamandis and James Cameron.
In 2012, they revealed their plan to the world.
Under the banner of a new company, Planetary Resources,
they would mine asteroids for their precious resources
and perhaps save the world along the way.
The richest person in modern history
was John Davis Rockefeller.
His net worth was three times greater
than that of our richest tech billionaires,
inflation adjusted.
And the source of that fortune--
timely exploitation of a vast, then-untapped natural resource,
oil.
Well, the days of oil may be numbered,
but there's another natural resource
that's never been touched, is effectively inexhaustible,
and has a dollar value large enough
to disrupt entire economies.
That resource-- asteroids and the precious materials
they contain.
Astrophysicist Neil deGrasse Tyson
predicts that the world's first trillionaire
will be an asteroid miner.
The Rockefellers of the 21st century
may be less like the internet and tech
moguls of the 20th century and more like the old-school oil
barons of the 19th.
But asteroid mining isn't the same as drilling a hole
and hoping black gold spurts out.
It will take years of work by dedicated engineers
and scientists and billions of dollars
to extract the first dollar's worth
of useful asteroid material.
So will it happen?
Can it happen?
To answer this question, we need to learn a bit about asteroids.
Asteroids, along with comets, are leftover material
from the formation of the solar system.
They range from a meter or so to hundreds
of kilometers in diameter, and they live primarily
in the asteroid belt between Mars and Jupiter.
There are also a few smaller groups
of asteroids inhabiting different regions and orbits
in the inner solar system, including
some that cross Earth's orbit.
As you'll see, these will become important.
Unlike the more-icy comets of the outer solar system,
asteroids are rocky or metallic.
They are the stuff of the terrestrial planets,
the building blocks of worlds like the Earth that
never managed to pull themselves together.
The most abundant asteroids are C-type or carbonaceous
asteroids, constituting 3/4 of all known asteroids.
They have high abundance of water, an extremely valuable
resource in space.
And I'll explain why in a sec.
C-type asteroids do contain some valuable heavy elements,
but not as much as some of the other asteroid types.
For example, S-type, or silicaceous asteroids,
they make up roughly 17% of the asteroids
and contain, you guessed it, silicates.
They're rocks.
They contain more-valuable elements than C-type,
so a good amount of iron and nickel,
and a smattering of more-precious stuff
that I'll get back to.
Third-most abundant are M-type asteroids.
That's M for metallic.
Most are big chunks of iron and nickel.
These are the leftover cores of larger asteroids that
were destroyed by collisions.
If an asteroid is massive enough,
it will undergo a process called differentiation.
During its formation when it's still
a giant bowl of molten space rock,
heavier iron and nickel will sink to the asteroid's center.
Smash that asteroid hard enough and you shatter it,
exposing a juicy, rich metallic core.
All asteroid types have the potential to be profitable.
The key to their profitability is the right combination
of valuable contents, mission-essential resources,
and accessibility.
Let's start with the good stuff.
What loot do asteroids drop--
well, definitely gold and platinum
and other precious metals.
It's not that there's more of this stuff in asteroids
than on Earth, it's just that it's more accessible.
See, the same differentiation process
that led to M-type asteroids long ago
sucked Earth's crust dry of many of these elements.
This is particularly true of elements
that alloy readily with iron.
They followed iron into the core or mantle
during Earth's formation.
This included gold, platinum, and silver,
but also key industrial metals like palladium, rhodium,
and iridium.
These elements are just more accessible in all
but the largest asteroids.
In fact, much of the precious-metal content
of Earth's crust came from old asteroid impacts.
The Planetary Resources company estimates
that a single 30-meter asteroid may contain $30 billion
in platinum alone, and that a 500-meter rock could contain
half again the entire world reserves
of platinum-group metals.
Kilometer-scale asteroids would be worth many trillions.
It's worth noting that the value of some elements like gold
and platinum are largely due to their rarity.
Asteroid miners are going to have
to be careful not to crash the value of these materials
with oversupply.
Perhaps the most lucrative asteroid loot
will be the stuff that's useful to industry.
That includes some of the aforementioned platinum-group
elements but also the rare-earth elements.
Both groups are essential in everything
from electronic components, batteries and fuel
cells, magnets, as chemical catalysts and reagents,
and in a huge range of advanced materials.
The technological world is utterly
dependent on these elements and becoming more so.
While rare-earth elements aren't actually
all that rare in Earth's crust, most
are dispersed in a way that makes sifting them out
not commercially viable.
Concentrated rare-earth mineral deposits do exist,
but those are genuinely rare, and the accessible supply
is running low.
Asteroids are literal gold mines for stuff
we want to bring back to Earth, but they also
contain materials useful for the mining process itself.
Raw materials like iron, nickel, aluminium, and titanium
are not cost effective to bring back to Earth,
but they can go towards building infrastructure
in space, including more asteroid-mining facilities.
But even more important is water.
Water dissociates into hydrogen and oxygen,
becoming rocket fuel, which is critical for shipping
mined resources back to Earth.
If you have to carry all that return
fuel on the initial launch vehicle,
you have to massively cut back on the amount of mining
equipment, and you also limit what asteroids you can access.
The perfect asteroid has a decent amount of water
but also a high abundance of valuable materials.
It also needs to be large enough to be worth the effort
and accessible by an economical spacecraft.
And eventually we'll probably see mining operations
in the actual asteroid belt where useful rocks are
plentiful, but to start with, it's much easier
if the asteroid comes to us.
Fortunately for asteroid miners, though less
fortunately for the dinosaurs, many asteroids
do cross Earth's orbit in their passage around the Sun.
Some of these near-Earth asteroids
can be accessed with relatively little fuel expenditure
from Earth orbit, and these will be the target
of the first missions.
Identifying the perfect easily recoverable object or ERO
is where a lot of the action is right now.
This asteroid prospecting is the current focus
of effort for Planetary Resources and its competitors.
We know of over 17,000 near-Earth asteroids,
but only a small fraction are likely to be cheaply
accessible, large enough, and have the right composition
to be worth the effort.
To be short of a profitable composition,
robotic prospectors are going to have to visit asteroids.
Planetary Resources is developing its Arkyd spacecraft
with that initial goal.
And its main competitor, Deep Space Industries,
is working on a range of low-cost prospector craft.
Interestingly, both of these companies
have significant funding from the Grand Duchy of Luxembourg.
Apparently this tiny landlocked nation
has some impressive cosmic aspirations.
So, let's say we find the right asteroid.
Then what?
Well, we can attempt to mine it on location, so
with the orbit of the asteroid, or we can nudge it
into a more accessible orbit close to the Earth,
perhaps even in orbit around the Moon.
This can be done with a gravitational tractor, which
we talked about before, or with rockets
fueled by the asteroid's own water supply.
Moving a near-Earth asteroid into lunar orbit
was the goal of NASA's Asteroid Redirect Mission,
but it was canceled in 2017 due to lack
of congressional support.
Shame, really.
It was one of the few missions that
had a clear track to massive potential profits
and saving the planet from asteroid impact.
Because if we learned how to land on and push an asteroid
to a different course, we could potentially
push an Earth-killing asteroid off course.
OK, we found our asteroid and sent our mining facility.
How do we harvest the goods?
It could be a simple matter of scooping up rocky material
from the surface.
Smaller asteroids are expected to be loosely bound rubble
piles, so breaking them apart will be relatively easy.
There are also proposals to scrape regolith, asteroid dust,
from the surface, or to magnetically harvest
loose surface metals.
There's also the Mond process by which carbon monoxide gas
reacts with nickel and iron to produce a gas containing
these elements.
This can then be collected and processed by the spacecraft.
Water is the easiest to extract.
It can simply be evaporated from the surface
and collected as vapor.
For larger solid asteroids, it may make sense
to actually tunnel into their interiors,
but that's a way down the track.
The first asteroid-mining missions
are slated for the 2020s, but the timetable is very loose.
Once the enterprise is demonstrated to be profitable,
you can be sure the real gold rush will begin.
Money talks, and tens of billions
or even trillions of dollars per asteroid speaks very loudly.
Perhaps in just a few decades we'll
have mining outposts in the asteroid belt.
The first effort will be purely robotic.
But as the industry scales up in the asteroid belt,
real-life human operators may be needed.
Who knows? perhaps season 30 of "The Expanse"
will be listed in drama instead of science fiction.
And with that abundant supply of resources
and without the insane per-kilogram price
tag of launch from Earth, perhaps the real work
can begin of expanding humanity's reach into more
distant regions of space time.
Today's episode of "Space Time" was sponsored by Audible.
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