Europa is cool and all but if there’s one thing even I can attest to…
“Halo” is waycooler.
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:
"Stars gives off all sorts of things besides visible light; heat is just one of them. The Hubble Telescope and the Spitzer Space Telescope are equipped with several tools that can capture ultraviolet light, infrared, and x-rays...along with visible light (obviously). If we spotted a section of the cosmos where a Dyson Sphere was in use, we would likely see something like a blackbody object that's radiating in the far infrared around 10 microns in wavelength. A perfect blackbody is a theoretical construct that, among other things, is a perfect absorber (meaning that it absorbs all wavelengths equally and perfectly). It doesn't reflect anything. A Dyson Sphere, which is meant to absorb all the light of a star, would be (in essence) a blackbody. However, if these perfect abosrbers just kept on absorbing everything around them, they would get hotter and hotter and eventually they'd get infinitely hot. That can't happen, which is why a perfect blackbody is just a theoretical construct."
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!
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!
- Wiki on Dyson Spheres
- Wiki On Solar Sails
- Interview with Neil Murphy of NASA about Solar Sail Technology
- Wiki on James Clerk Maxwell
- Information on SunJammer
- NASA blog on history of Solar Sails
- New World Encyclopedia entry on Pyotr Lebedev
- Space.com article on Dyson Spheres
- Wiki on blackbodies