Europa is cool and all but if there’s one
thing even I can attest to…
“Halo” is way
cooler.
With that I give you the Dyson Sphere. It’s a
technology so hypothetical that theoretically it could already exist. Is the
concept not making any sense to you? No worries. It confused the hell out of me
at first too.
Today at To Infinity and…In Theory we’re
going to discuss a growing energy crisis, what a Dyson Sphere is, how it works,
and how to look for something similar to this that may already exist.
Let’s start with the basics. What is a Dyson
Sphere?
Technically They’re
Stapledon Clouds…
Science Fiction has a tendency to become
Science Fact someday. It seems it takes quite the eccentric of an imagination
to dream up the advances of the future. The Warthog from Halo is one example.
Da Vinci’s flying machines and Jules Verne’s submarine are others. But in 1937,
a British author by the name of Olaf Stapledon wrote a colorful novel proposing
theories of the universe that were not only unknown at the time, but by today’s
knowledge, is mostly correct.
The most incredible of this were the unnamed
objects surrounding the stars of super-intelligent quadrants of the universe.
These “light-traps” gathered up all the energy supplied by the sun and utilized
it for the super-intelligent beings to harness for their technological
advancements. These “light-traps” are what we would probably refer to as solar
arrays today. The arrangement around the sun gathering all the energy, that’s a
different beast altogether.
Here’s the excerpt from his 1937 novel “Star
Maker”:
"Not only was ever solar system now surrounded by a gauze of light traps, which focused the escaping solar energy for intelligent use, so that the whole galaxy was dimmed, but many stars that were not suited to be suns were disintegrated, and rifled of their prodigious stores of sub-atomic energy."
Considering the time period that’s some
pretty advanced thinking. From that very clever description, when a young man
in 1945 read Star Maker, it gave him a brilliant idea. He realized we were
going about the search for intelligent life all wrong. If we wanted to find it,
we’d need to let Olaf take us all to school.
The Unwanted Legacy
of Freeman Dyson
While Olaf Stapledon’s wild imagination
dreamed up the initial conceptualization of these hypothetical megastructures,
a man named Freeman Dyson took the thought experiment one step further in his
1960 paper "Search for Artificial Stellar Sources of Infra-Red
Radiation", published in the journal “Science”. He didn’t outline how we’d
go about building one; he just focused on the most important aspect to him.
Energy.
He hypothesized that eventually as a
technological civilization advanced its need for energy increased exponentially
as well. Look at the time from the middle ages to the industrial revolution.
Horses and caravans gave way to steam engines and coal burners. Eventually
these were replaced with petroleum, and now we even find ourselves searching
for ways to get more energy than oil produces. Dyson certainly wasn’t wrong.
In a way he wished he had been though. In
2013 at a symposium Dyson was quoted as saying he wished he’d never been
credited with the fanatical science fiction fantasy concept. Perhaps he wouldn’t
have been if he’d have given Mr. Stapledon credit for his groundwork in the
initial paper. Alas, he did not; he did however think things through very thoroughly.
He described these as a shell that would
orbit the sun; the solar arrays would gather the energy and transmit 100% of
its power back to the Earth for our consumption. It’s a brilliant concept but there
are a million problems to overcome. First and foremost, there’s a little thing
called gravity.
The gravitational pull of the sun is around
28 times stronger than what we experience on the Earth. Without finding a way
to lock a satellite in place around the sun it would just be pulled into the
star and burned to a crisp. Several different patterns have been proposed, from
the Dyson Swarm, Bubble, and Sphere, all the way to an entire enclosure around
the star that doubles as a habitat for the intelligent species. This is
probably the least feasible but the others actually might not be too far from
something golden.
Let’s break down this fiction into fact-tion.
Come Sail Away
Above we mentioned
that in order for these satellites to gather energy from the sun directly they have
to be able to counteract it’s incredibly strong gravitational forces. Amazingly
enough, the concept has been around for hundreds of years. Let’s go back to the
1800s and visit a man named James Clerk Maxwell.
James Clerk Maxwell
discovered what is often referred to as the second great unification of
physics. Combining optics, electricity, and magnetism he discovered that these
all had similar properties and worked in tandem with one another. In 1861 James
Maxwell wrote his findings on electromagnetism.
An incredible
mathematician, as well as a physicist, Maxwell came up with a series of 20
equations and 20 variables that were published in 1861 that proved electricity,
magnetism, and light all played a role with one another, and all could be
manipulated from pressures and were capable of providing momentum. Through
this, by 1864, Maxwell had theoretically described the ability to use light
pressure in order to sail.
That’s when an
author by the name of Jules Verne took it a step further (as they so often do)
and decided that using light pressure to sail the oceans was boring, but in
space on the other hand, "there will
someday appear velocities far greater than these [of the planets and the
projectile], of which light or electricity will probably be the mechanical
agent ... we shall one day travel to the moon, the planets, and the stars."
This is often considered to be the first written account of using light sails
for, well, sailing.
Well all of this
was fine and dandy but there was a slight problem. While James Maxwell’s experiments
and papers were very well thought out and conducted properly, he was limited by
what he had available for equipment at the time. His theories were widely
accepted, but they were still not considered by all as definitive. Then in
1899, a Russian scientist blew everyone away and would’ve made Maxwell very
proud.
A man named Pytor
Lebedev, a man without even a high school diploma, found himself pondering the
thoughts of Johannes Kepler one day. In 1619, Kepler came up with a theory that
radiation pressure had to exist in order to explain the way a comets tail
always points away from the sun. As we know now, the tail of a comet is a
mixture of ice particles, minerals, and various gases, which explains how
radiation pressure is able to have an effect on it.
Using a device he
created capable of producing light waves of 6mm and 4mm, and a Nichols
radiometer he proved the existence of radiation pressure. Through this he also
proved Maxwell’s theories. Experiments in following years would build upon this
concept much further until the point where we reached the Solar Sail.
Flashing ahead to
1974 we’ll take a look at the Mariner 10 mission. This satellite mission was
unique, not in the reason it was in orbit, but the understanding scientists got
from some on-the-fly maneuvering. When the satellite’s stores of attitude
control gas ran low and the risk of being dead in the water was becoming a very
real threat, NASA control came up with a brilliant idea. By angling the solar
panels at the sun at a precise angle they were able to use the minimal amount
of radiation pressure exerted on this particular craft to create attitude
control. Mariner 10 wasn’t designed for solar sailing, which by the 80s had led
many scientists on the quest to replicate the events of Mariner 10, but more
successfully.
The Russians
attempted solar sailing missions throughout the 1990s with mixed success. The
first one that went up into orbit unfurled and was able to beam solar energy
back to the planet but it was unable to control itself in orbit and burned up
in the atmosphere. In 1999 the successor to this mission failed to deploy
properly and the Cosmonauts abandoned solar sailing.
The Japanese in the
early part of this last decade deployed solar sail missions into space as well.
In 2003, India also deployed solar sails as supplements to some of their spacecraft’s.
It seems Photon Sails were all the rage. But there’s one problem, they haven’t
technically been considered a success, because so far they haven’t technically worked…
While solar sails
have yet to be used in space as a means of propulsion, NASA is hoping to change
that by 2015. The SunJammer mission slated to launch then hopes to be the first
successful attempt at using photons from the sun’s rays in order to gain
momentum. Only time can tell if this will work out for us, but one thing is sure
if it does, we’re one step closer to a Dyson Sphere.
So that’s just one problem. The next is
weight. As we all know the more dense an object is, the stronger the effect
that gravity has on it. This is apparent in the difference between a feather
and an apple. If both are dropped from the same balcony the apple will most
assuredly hit the ground first. Why? Because it’s heavier, it has more density.
So how do we lower the effect of gravity on our solar sails?
Nanotech
for Macro Problems
We’ve talked about the potential for using
Multi-Walled and Single-Walled Carbon Nanotubes here before at TI&IT (Nano-Tech: Big Problems, Small Answers) for applications in the medical field via
cancer treatments. But we also talked about them having a multitude of
applications. Well today we’re going to go from the terminal ward to the outer
reaches of space. Turns out MWNTs (Multi-Walled Carbon Nanotubes) are going to
be setting sail.
Nanotubes have some serious benefits. They’re
light, durable, extremely tough, and very thin. This means a bulletproof vest
that once weighed fifty pounds can now weigh less than eight ounces. To go
further with this example, this means a glass and panel solar satellite that
once weighed thousands of pounds is now capable of weighing as relatively
little as an average human being.
In fact, some scientists predict that using
MWNTs in the production of solar sails could lead us into the age of
interstellar travel. Some estimate that the sails will be capable of reaching
up to 5.6% the speed of light under the right conditions. Being that my
mathematical background is rather limited, I’m not at liberty to discuss the
complex equations leading to these discoveries, but I trust the community for
the most part.
And the use of nanotubes doesn’t have to end
in the construction of the sails. They can be used to craft the vessel attached
to the sail as well. Solar sails don’t have many moving parts and using all
natural propulsion offers a secondary group of long reaching advantages, the
biggest of which being longer running time.
The last hurdle to really overcome is the
ability to beam the light back to the Earth for us to use. However, major
advances in solar technology have made this once significant issue far less of
a problem. We’ll have to wait till 2015 to see if the solar sail works, but if
it does, let’s take a look at some of the ways we can use this to create our
hypothetical Dyson Sphere.
Swarms, Bubbles, and
Shells
The first and possibly most complex of the
three forms we’re going to talk about is the Swarm. The easiest way to
accomplish this would be to make a ring (Think the Forerunner’s “Halo” in…ya
know…”Halo”). To just make one single ring, while it would be the easiest
pattern for astrophysicists and mathematicians to work with, it wouldn’t be the
most energy efficient.
The one pictured above however would be a
much more proficient form of a swarm. The problem with this nevertheless is
that it involves extremely complex patterns of movement for each solar sail. At
certain points the satellites will overlap with each other and run the risk of
catastrophic damages if they should collide with one another. The precision for
calculations in this format leaves absolutely no room for human error.
But the next form of a Dyson Sphere…
…solves
the problem of complex overlapping orbits by having no orbit whatsoever. In the
Dyson Bubble structure all the satellites are fixed in place using
countermeasures built into the solar sails. While the ability to lock “statites”
(Stationary Satellites) around the sun is beyond modern engineering capabilities,
it cannot be ruled out as a potential candidate.
The third example still, the Dyson Shell
(other than the Galactic level Dyson Sphere) is probably the least probable of
all these.
The Dyson shell would encompass the entirety
of the star, thereby harnessing 100% of its energy. The tricky issue with this unfortunately
is that in constructing something of this magnitude, the civilization would
displace all the suns light. This could prove catastrophic for any life on the
surrounding planets that rely on the sun to produce energy for their survival.
Hence why when a Dyson Shell is suggested in Science Fiction novels, typically
the race that built it has also built a habitat within the shell.
Other suggestions have been put forth for
other Dyson related constructs, including Stellar Engine refueling stations and
the improbable “Dyson Net”, and I’m sure more will be put forward in the future
until we have actually achieved this pinnacle of technology.
Now that we know what they are, how they
work, what we’d need to build one, and some of the variations, let’s talk about
the most important two questions of all. What kind of civilization would have
one of these and just how would you look for one?
Looking
For a Grain of Sand on a Beach
SETI (Search for Extraterrestrial
Intelligence) has been searching the heavens above for decades now. Other than
a few strange signals though, they’ve mostly come up with nothing. However, a
researcher named Geoff Marcy has an answer. He thinks we’ve just been looking
all wrong. We need to re-evaluate what it is we’re looking for.
He suggests we turn to the heavens and search
for what is known as a blackbody. A blackbody is a hypothetical construct that
absorbs all light in a given area. In essence, since a Dyson Sphere is meant to
absorb 100% of a star’s energy, it would be classified as a Blackbody. One of
my favorite publications, “From Quarks To Quasars” explains it best:
So what kind of world would use this method
of harnessing energy? Well according to Soviet Astronomer Nikolai Kardashev, a
Type-II Civilization would be capable of completing such a daunting task. The
problem? We’re still considered a Type-I civilization on the Kardashev scale.
They don’t estimate us reaching Type-II for another thousand years (ouch…) to
learn more about this very real scale Kardashev devised you can visit Wikipedia
by clicking here.
I would love to see a Dyson Sphere of some
kind in my lifetime, but for now I’ll settle for a successful deployment of a
solar sail next year. We’ll probably be covering more about solar sails in the
future so stay tuned for that! Thanks for reading everyone! Hope you had a
wonderful Memorial Day!
-Ryan Sanders
To read more about
any of the topics we discussed above today feel free to visit any of the links
below. As always, thanks for reading, and Happy Learning all!
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