Dyson’s Folly — If you build it, we will come: The search for extra-terrestrial intelligence

Ever since we have known that Earth is a planet, and is only one of countless others in the universe, we have been pondering the possibility that life may exist on those other distant planets.

It seems unlikely that we are the only life in this huge universe, yet that could very well be the reality. Still, we forge ahead, hopeful…even wishful…that we are not alone. “Seems unlikely” is really all we have to go on. With no evidence—there is not the slightest indication that life exists elsewhere—we don’t even know what look for.

In 1877, astronomer Giovanni Schaparelli discovered what appeared to be canals on the surface of Mars. His drawings depicted a series of straight, crisscrossing dark lines that did not appear to be natural. Speculation about their origin ensued, and interest in extraterrestrial life skyrocketed. We now know that no canals exist on Mars, and to this day, no one knows exactly what Schaparelli saw, but with the subsequent discoveries of many more planets in distant star systems, the interest in finding other life forms elsewhere in the universe has not waned.

150 years after Schaparelli’s observations, we are now able to send probes to the other planets in our own solar system, and in some cases obtain and analyze samples. Still, no signs of life have yet been discovered on any planet but our own. We have found some of the “building blocks of life,” chemical compounds essential to Earthly life forms, but none of those chemicals have assembled themselves into anything resembling life. You can go to any rocky planet and find the building blocks for a stone wall, but none have been assembled into a stone wall.

The planets that we have identified in distant star systems are too far away for any current probes to reach in anyone’s lifetime. We cannot directly detect the presence of life, or even the building blocks of life on those planets. We assume that life may have evolved on planets with conditions similar to the only planet that we know has life: Earth. For that reason only, we are looking for Earthlike planets that are in orbits within the so called “Goldilocks zone”. That zone is defined as an orbit that is close enough to its star to receive abundant light and energy, but not so close as to burn it up. Not too hot, not too cold.

But why are we limiting our search? Our own home is an Earth-like planet in the Goldilocks zone. It has existed for 4.5 billion years, and as far as we know life spontaneously erupted here only once. Conditions were right only one time, for a very short time, in 4.5 billion years. We have no evidence of any other genesis on this planet, yet we are looking for Earth-like planets in other solar systems. If Earth is so conducive to the genesis of life, why is there evidence of it happening only once?

Another thing worth considering is the fact that Earth was a very different planet 4.5 billion years ago. It was not Earthlike at all by today’s standards. Many of the changes Earth has experienced were a direct result of the life that existed very early in our planet’s history. Early life forms radically altered the chemistry of our atmosphere. If life had evolved differently, Earth itself could be very different today.

What are the chances that there is only one planet in the universe that harbors life, and we just happen to be on that planet? That is not science. That is backward logic, yet that is part of the rational for searching for planets in the Goldilocks zone.

So far the only evidence we have of life anywhere in the universe is from one planet, and every other planet we have discovered has been different—different from ours, and different from each other. Every star is different from our sun. Every star system is different. It is very possible, and perhaps even expected that if life did crop up elsewhere, it would be on a completely different type of planet, with a very different environment that allows different biological processes to evolve.

We expect any planet we find to adhere to the same chemistry and physics rules we have observed here on Earth. That’s probably logical as those laws appear to be universal, but can we also expect life forms elsewhere to follow Earth’s biological rules, using the same chemicals, proteins, amino acids and DNA? There is no guarantee, and very little reason to even suspect that would be the case. Life will very likely be unimaginably different, possibly unrecognizable to us as life.

Even if life exists on any of those planets we consider Earth-like, we likely won’t see it unless it is vastly larger than anything we know, so we are developing different ways to search for life. We may be able to detect living things that have become advanced enough to build things. So we look for observable signs of technology. We are, in a sense, looking for the stone walls.

One possible sign of technology would be radio waves. Since the early 1900s, almost as soon as we could send and receive radio transmissions, we have been listening for radio signals and other electromagnetic radiation from space. It’s possible other advanced civilizations have used radio waves for communication. Our own radio-frequency emissions have been traveling through space for over 100 years. Those earliest transmissions have traveled 100 light years. That’s far enough to have reached 10,000 other star systems. We could also have received radio signals from any planets in those star systems that originated at least 100 years ago.

So far we have received no signals that seem to be generated by another intelligent life form. There are 1300 star systems within 50 light years from Earth. If anyone had replied to a signal from any of our earliest radio transmissions, there would have been enough time for that signal to reach us.

In the one hundred years we have been actively monitoring radio waves from space, we have detected none that seem to come from another intelligent source. That’s not to say we haven’t received signals from another civilization, only that we have not recognized it as such. They likely won’t be speaking English.

Perhaps they are advanced enough to visit us. That would certainly save us a lot of effort.

We have been chasing UFOs since the 1950s assuming—hoping—that some may be piloted by interstellar travelers. To this day there is no evidence that Earth has ever been visited by beings from another world. Nor is there any evidence of unmanned technology, such as probes, sent by beings from any other planet. First-hand descriptions of flying saucers and alien abductions notwithstanding, there exists zero evidence, let alone proof, of alien visitation on our lonely little planet. They probably didn’t build the pyramids.

They have not sent us radio messages. They have not visited us. We can’t see them. Still, we want to believe they’re out there, somewhere. What do we look for now?

Perhaps an advanced civilization had a need to build something really, really huge, big enough to detect from Earth, a structure that could not have formed naturally. It would need to be much larger than our metaphorical stone wall. Our own civilization does not have the resources or the technology to build something big enough to be seen from another star system, assuming a civilization existing there was no more advanced in their observational capabilities than we are. But we can imagine it, so it must be true.

It is in that spirit that we are now searching for evidence in other star systems of something from a uniquely earthly source: literature. Astronomers are currently scanning the heavens for something that was first described in a work of science fiction.

In his 1937 novel, “Star Makers,” Olaf Stapledon imagined a distant civilization building a huge reflective shell-like structure that could be used to redirect radiation from a star to their planet, providing more energy to feed their power-hungry technology.

About 20 years later, in 1960, theoretical physicist Freeman Dyson was fascinated by the notion and after doing some arithmetic he postulated that it was possible. This imaginary mega-structure has now become known as the Dyson Sphere.

A Dyson sphere is a structure or system that completely envelopes a star and the planet of its builders. Mirror-like reflectors in that system capture the light and other electromagnetic energy from the star and redirect it toward receivers on the planet, thereby harnessing more of the star’s energy than would ever naturally reach the planet.

Scientists theorize that such a structure would be large enough for us to detect, indirectly, as portions of it passed between the star and Earth, temporarily blocking some of that star’s light from reaching us. We would see it as a periodic dimming of the star. The structure would likely also emit some detectable infrared radiation.

To demonstrate the immensity required of such a structure, and the overall magnitude of the project, let’s imagine the hurdles of building one in our solar system for our own growing energy needs on Earth.

As described in the novel, this sphere would need to be large enough to encompass the sun and Earth, so the outer edge of the shell would be located somewhere between the orbits of Earth and Mars, at a distance of around 100 million miles from the sun, give or take a few feet. That would give it a diameter of 200 million miles and a surface area of a whopping 100 quintillion square miles.

Even if the sphere were just a system of individual satellites, rather than a complete shell-like structure, which is very likely impossible anyway, that is a vast area to cover.

So, let’s start small. We will instead launch a bunch of individual satellites to orbit the sun somewhere between Earth and Mars. It will be ring of individual satellites around an orbit that is 700 million miles long. 700 million miles!

If the satellites in that ring were spaced 10 miles apart, that would take 70 million satellites, each with giant mirrors to reflect solar energy to Earth. And that would require as many as 70 million receivers on the ground to collect and process that received energy.

Also, each satellite is orbiting the sun, not in a fixed position relative to the Earth or sun, so its position and attitude relative to Earth is constantly changing. Each orbiting reflector would need to be constantly adjusting to keep it pointed toward the Earth and sun at the proper angle to maintain a steady flow of energy directed to a single point on Earth, the energy receiver, which would also need to be constantly moving.

The closest to Earth any one of those satellites would be at any given time is about 20 million miles, the furthest, over 200 million miles. At any given time, most of the satellites would be over 150 million miles from earth.

The size of the mirrors or reflectors would dictate how many would be needed to direct enough energy toward Earth to make a difference. Naturally, the larger we can make them the fewer we would need. 70 million is a lot of satellites, but how large can we make them?

To get some idea of the size necessary for the reflectors, we can look to the moon for comparison. It isn’t an efficient reflector, but we can get an idea of the scale.

The moon is 2000 miles in diameter and only a quarter of a million miles from earth. That is huge compared to the size of any reflector we could build, and 20 million miles closer than the nearest Dyson reflector would be. How much usable energy are we currently collecting from the solar energy reflected off the full moon? It’s enough for really good photographs of the moon, but not enough to power the camera taking the pictures.

By contrast, Mars’ diameter is twice that of the moon, and at its nearest approach it’s at a distance that many of the closest Dyson satellites would be at any given time. Viewed from Earth it is just a pinpoint of light. How much energy could we receive from that pinpoint? Even if it were a proper reflector, rather than a reddish-brown ball, it would be a pinpoint, a very bright pinpoint, but still a pinpoint. That would not charge my cell phone.

If each reflector was 4,000 miles in diameter, roughly the size of Mars, it would take 175,000 of them, orbiting side-by-side, to complete the ring.

This is a huge undertaking. Massive amounts of materials and energy, as well as perhaps hundreds or thousands of years would be required to accomplish this.

If you have the energy and other resources that are necessary to build such a system, you don’t need the system.

But, let’s suspend reality for a moment—it is science fiction after all—and assume we could do it. Let’s say we now have a substantial amount of energy directed toward Earth from the sun. The energy we currently get from the sun is just enough to sustain life and maintain healthy ecosystems and weather.

That extra energy directed to the Earth by the orbiting Dyson satellites would have the same effect that moving our planet closer to the sun would have. It would quickly heat our atmosphere and fry our lovely planet to a crisp. Goldilocks would be eaten by the three bears.

The following is a summary of Dyson’s Folly:
1. Assume, with no evidence, there is life elsewhere in the galaxy.
2. Assume, with less evidence, that the life form is intelligent.
3. Assume that life form has a civilization that has developed technology far beyond our own.
4. Assume they need more energy to power that technology than their planet receives from their star.
5. Assume they have chosen a solution from a science fiction novel that was written hundreds of years in the future on a planet hundreds of light years away.
6. Assume we can scan the heavens looking for signs of that fantasy structure, which would only suggest the possible existence of something for which there is no evidence.

That is simply too much pretending to be real science. There is precious little science to back up any of those assumptions.

With all our imagination, we can’t seem to grasp the concept that something alien is likely to be alien, and as such, unimaginable.

We also seem to forget what circumstances allowed us here on Earth to develop our own technology.

For over 99% of human history, humans depended upon fire for their energy needs. That fire was possible only because of combustible plant life. Fossil fuels were eventually discovered and exploited, fuels which also derived from plants and animals. It took millions of years, and a set of very specific circumstances on Earth to make that fuel available. What are the chances that might happen somewhere else? That sequence is quite possibly unique to Earth’s history.

If a developing intelligence on another planet needed energy, where might it be found?

We are lucky to have had a plentiful source of fossil fuels. We are where we are today only because of fossil fuels, and abundant trees to burn before that.

If our early human ancestors had not had wood to burn, how would they have kept warm as they migrated to cooler climates? How would they have cooked food? How would they have processed and used metals? What energy source would have led to technological innovations? Water power and wind power need at least some technology to harvest and utilize. We owe everything to our now-dwindling supply of fossil fuels. We are only able to use other sources of energy because they were developed with the benefit of fossil fuels.

Earth began forming over 4.5 billion years ago with random collisions of random space schmutz orbiting a still-forming brand new star. Earth had barely coalesced when it suffered a random cataclysmic collision with another large conglomerate of random space schmutz, which transfigured Earth and allowed its moon to form. The moon turned out to be an incredibly important, perhaps necessary development for life as we know it.

A little over 4 billion years ago, the first life randomly appeared on an Earth totally unlike the Earth humans have known for the last 300,000 years.

No one knows exactly when, where or how that first life came to exist, but 4 billion years later, and untold trillions upon trillions of random changes to Earth and everything on it, here we are, looking for some place else where all that randomness was identically repeated. I have to say it: That seems unlikely.

We don’t really know where to look. We don’t really know what to look for. We don’t know if we will know it when we find it. But the search continues.

The Dyson Sphere conjecture is science gone astray. But scientists—in this case, “science fictionists”—are reluctant to abandon their pet projects. Certainly a civilization advanced enough to build such a structure will have figured out how to avoid building such a structure. They will have eliminated the Rube Goldberg machinations from the process and developed a much more streamlined and efficient access to abundant energy.

Before we go, since we are looking to science fiction in our search for extra-terrestrial intelligence, we should not ignore all the grim warnings the genre has offered. Remember, the vast majority of human encounters with aliens have not gone well, for us or them. We have nothing to compare us to yet, but we should consider the possibility there is another civilization out there as blood thirsty as we are.

Also remember, if we can find them, they can find us. Rather than advertising our presence, it might be prudent to look for ways to make ourselves invisible to other civilizations, possibly borrowing another technology from science fiction: a cloaking device.

Because it is what we do, we will continue our anthropomorphic search for life, Sci-Fi Field Guides in hand, boldly seeking to turn fiction into a reality that ultimately leads to our own doom.

Be sure to tune in for the next exciting chapter in the search for extraterrestrial intelligence, as astronomers tear another page right out of science fiction history: “Finding the Death Star.”

© Scott Wright 2024

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