Understanding Alien Psychology

I have been thinking and blogging about the potential for finding and understanding aliens a lot recently, ever since reading Avi Loeb’s book on the interstellar object ‘Oumuamua, Extraterrestrial: The First Sign of Intelligent Life Beyond Earth. Now I am heading into realms that are totally unknowable—except from the viewpoint of what we know on Earth. But bear with me …

First off, I am not too interested—well, very, but not for the purpose of this meditation—in simply finding signs of life. We’ve seen things that could be confused with fossilized cells in the surface geology of Mars, and we suspect we might have found gases that could only be created by life-as-we-know-it in the atmosphere of Venus. When we get to other planets, both in this solar system and around other stars, we may well find chemical reactions and physical structures that we, from inside the realms of earthly biology and human understanding, define as “life.” Some of it may be intelligent but a lot of it, like most of the living forms on Earth, will not be what we choose to call “intelligent” or even “sentient.” Slime molds, for instance—honking huge single cells with eukaryotic nuclei—can move toward food and away from irritants in a fashion that seems to be intelligent or at least resembles neural networking.¹ But it’s not going to build a rocket and come visit us.

When I think about aliens, I imagine the kind that will leave their planet and come out among the stars, as so much of Western-civilized humanity apparently hopes to do one day. And until we go out there, we’ll just have to wait for them to come to us.

So, first question. Will they look like us? Or even come close—like the various humanoid species that populate a Star Trek episode? I don’t believe it. As Carl Sagan once said, we’d have more success mating with a petunia than with an extraterrestrial lifeform.²

Earth has a long history of large, active lifeforms that might have developed intelligence but as far as we know did not. The dinosaurs come to mind: the family Tyrannosauridae and their cousins were bipedal, oxygen breathing, hunters and perhaps also scavengers, and probably—maybe—at the top of their food chain. But we have no evidence that they exhibited any real intelligence greater than that of a lion or house cat, wolf or dog, or even a shark. And yet the dinosaurs’ distant progeny, the Corvidae family—crows and ravens—as well as many other species of birds have a kind of intelligence we cannot explain. Even octopi—what? a mollusk?—exhibit a high level of intelligence. So size, shape, and mammalian ancestry are not necessarily prerequisites for intelligence. Still, none of these animals from Earth and its history is going to build a radio or a rocket anytime soon.

But the examples from Earth also suggest that we cannot expect to find our own kind of intelligence out among the stars, even if it wears an unexpected shape or inhabits an environment—like the earthly ocean of octopi and whales, or perhaps the liquid water under Europa’s ice, or the methane seas of Titan—in which humans don’t particularly thrive. Life on Earth did not, after all, start out on the land, although that’s probably the best place to build a radio or launch a rocket above the atmosphere.

One particular axis we are likely to encounter in alien psychology is that between the individual and the group. So far, on Earth, the sort of intelligence that is likely to expand to encompass curiosity, technology, and eventually space travel is fixed in individual entities. We humans are separate and complete persons inside our own bodies. We are socialized into groups, certainly, in which we can function for enhanced performance. But we do not become lost, stricken, enfeebled, and die when separated from our group—or at least not right away. And we see this pattern not only in human tribes but also in monkey troops, wolf packs, whale pods, cattle herds, and other social groupings.

Each of us knows or tries to find our place in the group, establish a niche where our capabilities and levels of aggression or empathy best fit, and seek comfort and contentment—or at least a subdued level of rebelliousness—in that placement. We are social animals. And that is the basis of all culture and intergenerational achievement. The fabled lone wolf, the mad scientist, the antisocial genius who works alone and keeps his notes in a secret code—such beings are of interest to us as fiction but they are not the creators of lasting culture or enduring civilizations. They build no great cathedrals, establish no great cities, lead no great social or political movements—and they don’t send rockets to the Moon.

So, we think, the kinds of intelligence we will find out among the stars will be like us in that: socialized individuals, each with his, her, or its own personality, preferences, anxieties, and dreams.

But we have another example on Earth to draw on: the hive mind. Whether in the beehive, the anthill, or the termite colony, the individual entities—the minds inside the separate bodies—are not really individuals as we humans understand the term. They are physically adapted to their tasks and place in the hive structure, and their minds are shaped—one might say innately programmed—to perform those tasks and not question their role. Even the queen is not a ruler or leader but simply the pampered sexual progenitor, the mother of them all, that ensures the colony’s survival and renewal.

Something of this was captured in the movie Star Trek: First Contact, where we are introduced to the Borg Queen (pictured nearby with Alice Krige playing the part). But although the Borg are a collective of mechanized humanoid lifeforms whose brains are electronically networked, they are not really a hive and the queen is not their mother nor their first member. The queen speaks with a voice and persona that can call up the collective mind but can also examine it, see its options and possible choices in context, contrast their existence with what she knows of humanity, and evaluate the Borg from the outside. She is more like a leader or first speaker than the sexual progenitor of the collective.

When we look to more imaginative literature on the idea of the hive as a society, the offerings are few. To my thinking, Frank Herbert has done some of the best work on this. His novel Hellstrom’s Hive examined what it would take to change human beings into the sort of social insects that could function most efficiently in the politically denuded world. And his novel The Green Brain imagined a hive of Amazonian insects that functioned as a single conscious entity, in the same way that the cells in our human bodies work together to create the reality—or perhaps it’s just the illusion—of a single person with independent will and desire.

We might encounter some variation of this colony structure, this collective intelligence that is not separated by the strands of individual personhood, out in the universe.

The question in my mind is whether this kind of intelligence is creative or merely reactive. A colony of honeybees or ants can adapt to its environment, find flowers or other foodstuffs when the weather is right, make its nest or hive nearby, and deal effectively with changes in environment and temperature, or else swarm to find a new nesting site. But can they only think and react to present and immediate needs? Could they eventually engineer changes in that environment? Could they look beyond the immediate locale and imagine ways to make it different? Could they look out at the stars and dream of visiting them? Or are they bound to the world as they know it, in a way that human societies are not?

Every group of socialized individuals is built of both leaders supported by their pack of generally submissive followers and then the potential outsiders, the rebellious youth and the mad geniuses, who question the social order, its structure and purpose, and seek something new or just different. At least, that’s how the human tribe has functioned and flourished. That is how we broke the bonds of merely reacting to our hunter-gatherer environment, engineered a better life through agriculture, created written records to preserve intergenerational knowledge, adapted invention and technology to improve everyday life, and then looked outward to the stars.

In our experience, based on that group of socialized individuals, progress depends upon imperfections in communication, upon differences of opinion and individual dreams, upon disagreements and conflicts. These are the one thing that the anthill or the beehive cannot survive. The resolution of these disruptions is never pretty and neat, and it’s never complete and finalized.

But without disruption and disquiet, you have the structured cooperation, the orderly processing and virtual stagnation, of the colony animal. That, or the brainless neural-net reactivity of the slime mold. And neither of them, I warrant, will be coming here anytime soon.

1. See, for example, Mycologist Explains How a Slime Mold Can Solve Mazes, from Wired.com in 2019.

2. But maybe we are connected after all, as in the panspermia hypothesis. See, for example, my meditation on The God Molecule from May 28, 2017.

Understanding Alien Technology

Recently¹ I reported on the interstellar object ‘Oumuamua (“oh-moo-ah-moo-ah”) and why astronomer Avi Loeb believes it to be a piece of alien technology instead of a wandering asteroid or comet. Because of his prior involvement in designing a project to send probes to a nearby star using lasers and lightsails, and because of ‘Oumuamua’s apparent similarity to one of these lightsails, Loeb accepts this as the possible explanation for an object of extremely light weight, flattened structure, and high reflectivity. He does, however, admit that this is only a comparison, and the object could certainly have other technological explanations.

While I accept his analysis of ‘Oumuamua from what we could detect at the time of its passing, I am powerfully reminded that we probably cannot understand or even guess at the nature of a piece of technology arriving from an advanced, spacefaring civilization. And I base this on the great technological divide that exists in our own recent history.

As I’ve written several times elsewhere, you could bring an educated first-century Roman forward in time to Europe in about the eighteenth century, and he could easily recognize most of what he saw. Styles and techniques would certainly be different in fabrics, clothing, and other everyday items like modern carriages, the tack of the horses pulling them, and the roads they drove on. He would have some trouble with understanding the widespread nature of a printed book but could easily understand the principles involved, once they were explained to him.

Our ancient Roman would have a somewhat harder time with a flintlock rifle, because his era knew nothing of gun powder or indeed had any experience with small, contained explosions—although they were familiar with volcanic eruptions. But without going into the structure of atoms and the chemistry of molecular bonding through the trading and sharing electrons, you could tell him the explosion was a kind of very rapid burning, and he could accept it. In fact, I suspect many people today without formal education understand most explosions as such. And as for the rest of eighteenth-century technology, the ancient Roman could be brought up to speed in an afternoon.

Now consider that same Roman brought into the world just two centuries later. Photography, recorded music—even in their analog versions, let alone modern digital transmission and storage—and other technologies we all have taken for granted since childhood, some of them since the dawn of the twentieth century, would be perplexing to him. Try explaining a light-sensitive film emulsion or the technique of recording sound waves on a vinyl disk, and you must first explain the physical wave properties of light and sound. Well, yes, start with ocean waves and work your way upward. And then go on to electricity and its relationship to lightning bolts. Then there are photons, radio waves, and the whole business of radio and television. Don’t forget electric circuits and transistors—the backbone of digital technology. Oh, and the steam engine and internal combustion, automobiles and airplanes. Not to mention microbes, cellular biology, evolution, and genetics.

It would take a couple of days just to catalog all the realms of science over which your ancient Roman temporally jumped. It would take several months of general science courses before he could even begin to understand the physics, chemistry, and other discoveries behind these technologies. Otherwise, it would all be magic involving either godlike or demon-inspired forces.²

If you doubt this, let’s try a thought experiment. Go to your computer, run a Google search on some topic—let’s say “Henry II of England”—and print out the results on your laser printer. Now get into your time machine and go back to a period after that Henry but before Gutenberg popularized printing and books in the mid-fifteenth century—say, the court of Henry III (reigned 1216 to 1272). Hand that printed page to any scholar or monk within reach. The monk would have the most experience of reading and writing, because he probably spent part of a day copying out the holy books. Let’s not ignore the fact that the English language has changed remarkably in diction, definitions, spelling, and orthography in the last seven hundred years, or that most of the people at court spoke a form of French by preference.

Your printed page would not be just a curiosity but practically indecipherable. The paper—at least of that uniformly high quality—did not exist in the West of that time. The fine and exact characters on the printed page would be unknown to people who dealt with handwriting, even with conscientiously practiced calligraphy and stone-carved inscriptions. And aside from the difference in language, the purpose of your printed page would be unguessable. Without a knowledge of the internet—whose technologies exceed even those we were trying to teach the ancient Roman—the listing and its references would be unimaginable. Even with an inkling of a world linked together with computers so that what any one of them knew could be known to any other, the functioning of a search engine like Google, and before it Magellan, Lycos, and AltaVista, let alone online bulletin boards like AOL, would take more than a day to explain and demonstrate.

Without such a guide and insight, your paper printout would be gibberish. Lacking the context of a search among dispersed references, the “message” would be incomprehensible as to its meaning and uses. What is “https://” or “www” or “.com” or “.edu”? Even if a monk could read beyond the language difference, these usages would be hieroglyphs without a Rosetta stone to put them in context. By itself, the paper would be an unsolvable mystery.

And so, while I can agree with Avi Loeb that ‘Oumuamua is likely a piece of technology—or technological debris—from beyond our solar system and therefore a sign of intelligent extraterrestrial life, I don’t think we will understand what it was used for. The analogy of a lightsail is extrapolated from technologies that we know and understand. But the reality, to us, might seem like magic. And even if we sent a probe out to capture the object or tear off a piece of it, we would still probably be in the dark.

We would have to wait to meet the aliens themselves and, like our ancient Roman, open our minds and really listen to their explanations. And only on that day would we begin to understand.

1. See Proof of Alien Life from April 4, 2021.

2. Arthur C. Clarke’s Third Law: “Any sufficiently advanced technology is indistinguishable from magic.”

Things Worth Believing

In the delightful movie from 2003, Secondhand Lions, a young boy is left for the summer in the company of his two granduncles, who may or may not have lived the swashbuckling lives suggested by their stories. The kernel of their existence, it seems, is embedded in the speech that one of the uncles gives him concerning “what every boy needs to know about being a man.” We never get the whole speech, but here is the part that’s given:

“Sometimes the things that may or may not be true are the things that a man needs to believe in the most: that people are basically good; that honor, courage, and virtue mean everything; that power and money, money and power mean nothing; that good always triumphs over evil; that love, true love, never dies … No matter if they’re true or not, a man should believe in those things because those are the things worth believing in.”

Wow!

We live in a cynical age, where most believe and repeat the thought that people left on their own recognizance are feckless and stupid, if not basically evil; where virtue is sneered at, courage is disparaged, and honor is a word out of the history books; where money and power are worshipped as basic goods to be obtained; where evil lurks in the heart of big corporations and/or big government, and these impersonal forces always win; where love is just another excuse for chasing after sex. In such an age, this speech by an old man should be held up to the light and examined, because it practically defines the idea of personal character.

We spend a lot of time these days trying to determine what is true, what is real, and too often what is useful. We forget that life happens in the moment. When a test of character comes at you, you cannot always be fretting about what may or may not be true. Usually, you can’t even know what’s true, or you don’t have the time to try to figure it out. In those moments that decide a person’s life, you just have to clench your jaw, set your mind, recall the things you actually believe in, and act as your better nature directs. And then you have to accept the consequences, come what may. Life is short. Character is all. And you never, or almost never, get a do-over.

So yes, sometimes you have to believe in things whether they are true or not, because they are necessary to good actions, proper choices, and happy outcomes. Also, because they are beautiful thoughts and will make you feel warm and secure.

But is this always the course to take? Should believing things, true or not, because these thoughts are worth believing, be the complete prescription for an examined life?¹ I think that opens a door into outer darkness.

For example, the belief in a personal, omnipresent, and omniscient god—whether or not it’s true that a great being exists outside of human space and time and watches our every move—does have a tempering effect on society. People seem to function better when they believe they live in a spiritual panopticon,² with someone, somewhere observing and judging their every action and holding them to a moral standard. It is also a beautiful thought that this universe has purpose, intention, meaning, and a conscious design; that life on this planet, especially human life, is more than just mindless growth, like bacteria or a tumor; that existence is more than circumstance, happenstance, and chaos; that someone, somewhere has a benevolent hand on the controls. As the 17th-century French philosopher Blaise Pascal is supposed to have said, “That’s the way to bet.”

But not everyone feels the need or perceives the active presence of a supreme being to watch over his or her actions and mete out punishment as necessary. Some of us have been raised in the humanist tradition, where reason and observed mechanisms of reciprocity and fair dealing govern our actions. And we are comfortable with the observations and hypotheses of scientific reasoning to determine what is actually going on in the universe, without the need for any guiding hand. So … is the concept of a benevolent, all-controlling, spiritual presence still something “worth believing” for these people?

For another example, the idea that human nature is perfectible—whether or not our actions and desires are partly informed by evolutionary biology, rather than a purely social construct that we can change at will—is an idea that attracts every generation of sociologists and political theorists. It is the beautiful thought that we, or some subset of human thinkers and activists, can create a paradise on Earth if only we can equalize human differences; eliminate the very human failings of greed and envy, anxieties about future security and personal advantage, and indeed all consciousness of self and family; and bring all humanity together by eliminating differences of opinion, the pursuit of private property and private enterprise, and adherence to national borders and national identity.³ This outcome would actually require rigid control of every aspect of life by the government or by a unified political party. But in the thinking and telling of these dreamers, the government itself withers away, people just become selfless and “good,” and all the turning points of human history—the crowning of kings, the wars of conflict and conquest, the disruptions of philosophical change and technological invention, the fluctuations of drought and flood, the surge and fade of the business cycle—all disappear into an endless, timeless human paradise.

But some of us value our own thoughts, ideals, and values, and we are not willing to give them up in the name of a presumed harmony. We value our freedom of action, while respecting the freedoms and independent agency of others, even if those freedoms lead to occasional conflicts and transient unhappiness. We love and strive for the safety and security of our families as the carriers of our unique genetic identity. We can recognize that people are different, and some of those differences result in groups, tribes, cultures, and nations that are not willing to sink into a homogeneous blandness, despite the promise of paradise. Although we recognize common traits among all human beings and common elements in all human societies, we still like to do things after our own fashion. Some of us are just stubborn that way. So … is the dream of a secular paradise through worldwide social and communal sharing still “worth believing” for the rest of us?

I could go on. Some ideas are so necessary and beautiful that they just have to be real, or you just have to believe them against a background of unbelief, chaos, and conflicting personal preferences. But beauty is in the eye of the beholder; so are truth and values. I find the sentiments of the uncle’s speech about manhood in the movie beautiful because they coincide with what I was taught as a child and have always felt. A serious religious thinker finds the invocation of a benevolent and all-powerful god beautiful because it is what he or she has always believed. And a dedicated socialist or communist finds the end of history in a form of secular paradise beautiful because the inconsistencies and internal failings of every other political and economic system are just too painful to imagine.

So … no. Some things are not to meant to be believed just because they are the things “worth believing in.” Or rather, they are not meant for everybody, not universal, and not to be rigidly applied. In this, as in every other aspect of human life, each person is required to pick and choose for him- or herself. All we can ask is that they choose wisely.

1. Socrates—that old rascal idolized by Plato—is supposed to have said at his trial, “The unexamined life is not worth living.” That thought, too, has shaped generations of high school and college students. It certainly shaped me.

2. That is 18th-century English philosopher Jeremy Bentham’s model of the perfect prison. The prisoners’ cells are arranged in a circle with the doors facing inward, each door with a covered spyhole, and a guard roving up and down the inner hallway, randomly observing and noting the prisoner’s actions. The prisoner never knows when he is being observed and might be called up for punishment. … And George Orwell thought he had a handle on repressive societal schemes!

3. Consider all the verses of the John Lennon song Imagine, which just about sum up all the attributes of a passionless human perfection. I’ve always found this song insipid, if not outright wrong-headed and stupid. And the tune is just mournful.

Proof of Alien Life

If you don’t read the science magazines, you may not be aware of the asteroid, or comet, or object that entered our solar system, passed around the Sun some months before October of 2017, and just as quickly went somewhere else. The object was spotted by the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) at Haleakala Observatory in Hawaii and was almost immediately identified as originating outside of our system—but only as it was already receding. Once so identified, however, it was given the designation 1I/2017 U1 and named ‘Oumuamua (pronounced “oh-moo-ah-moo-ah”), or “Scout” in the Hawaiian language.

Most astronomers consider it to be some kind of asteroid or comet, and the artist’s conception that was widely published (see nearby) shows a grayish or reddish oblong rock, clearly of natural origin. But let me be quick to point out that no telescope ever resolved the object’s image so clearly. All our telescopes could see—because ‘Oumuamua was already beyond Earth’s orbit when it was detected, and it was surprisingly small on an astronomical scale to begin with—was a faint point of light that varied in brightness over a regular eight-hour period. It was something really tiny and, by the time we saw it, pretty far away.

There the matter might have rested—a rock from beyond our solar system, an asteroid that had escaped from some other star system—if Avi Loeb had not taken up the issue. Loeb is an astrophysicist, an alumnus of the Institute for Advanced Study at Princeton, currently the Frank B. Baird, Jr., Professor of Science at Harvard University, formerly the long-serving chair of Harvard’s Department of Astronomy, and author of eight books of popular science and about 800 papers of serious scientific inquiry. He recently published his analysis of ‘Oumuamua, along with his lifelong involvement with the question of alien intelligence, in Extraterrestrial: The First Sign of Intelligent Life Beyond Earth (Houghton Mifflin Harcourt, 2021).

Being fascinated by the subject, I of course bought the book and devoured it right away. So consider this my book report on the subject. And accept that I find Loeb’s analysis convincing, even though most astronomers and cosmologists disagree and insist that ‘Oumuamua is still just a rock or other natural object.¹ Remember, I’m a natural contrarian.

The first issue is ‘Oumuamua’s brightness. The observations suggest that its longest dimension is just about one hundred meters, or three hundred feet, the length of a football field. I imagine such a tiny object would not normally be visible at interplanetary distances, the distance at which we first detected it, unless it was really bright. The nature of the light we could see suggested it was reflected sunlight, not any artificial light the object might be emitting. At that distance, the reflective capacity—called “albedo” by astronomers—had to be much greater than that of a rock or even the ice of a comet, which is usually so contaminated that we call them “dirty snowballs.” ‘Oumuamua reflects sunlight like polished metal.

The second issue is the shape. From the variation in brightness, the observations suggest that the object was slowly tumbling. The amount of reflected light varying over time implies that if ‘Oumuamua’s longest dimension is three hundred feet, then it’s shortest is a little more than a tenth to a fifth of that, or about thirty to fifty feet. The artist’s conception draws this as a cigar shape, and I think of it as about the size and dimensions of one of our nuclear submarines. But Loeb presents an alternative shape as more likely: a disk or a pancake. Here I am interpreting the reasoning as discussed in the book: if the oblong or cigar shape was the object’s true nature, then we would have to be viewing it practically end-on—that is, with the axis of spin at right angles to our line of sight—for the variation to be this complete. If we were viewing it from the side—with the axis aligned with our viewpoint—then the variation would not be as great. But a tumbling disk could display that degree variation from a variety of angles to our line of sight.

The third issue is the path that the object took in its travels. It deviated on its course around the Sun and accelerated slightly on its exit from the system. An asteroid, a solid rock, doesn’t do this but instead follows the course that its starting speed and the Sun’s gravity give it. A comet often deviates and accelerates slightly because sunlight heats the ice, causing outgassing that functions like tiny rocket motors, pushing the comet randomly this way and that and, on its outward trip, with the Sun at its backside, perhaps accelerating it. But ‘Oumuamua did not have a coma of dust and water vapor surrounding it or the long tail pointing away from the Sun, both features typical of a comet. Astronomers studied the object at various wavelengths—for example, in the infrared, where carbon dioxide from a comet’s emissions would show up clearly—and still they found nothing.

The scientists who dispute Loeb’s interpretation of ‘Oumuamua as a technological artifact suggest that it might have been composed entirely of frozen hydrogen, because the outgassing of hydrogen would be invisible to us. Such an object is possible, but it’s hard to imagine how, at the relatively slow speed it was traveling, such it would survive the long trip through interstellar space, where even starlight would eventually heat it up enough to melt it.

Scientists have also suggested that the object was pushed around and accelerated on its passage through our system by the Sun’s light itself. This idea is supported by the observation that ‘Oumuamua’s acceleration faded with the inverse square law as it went further and further away.² But for the object to respond like that to mere sunlight, it would have to weigh almost nothing. The rock depicted in the picture would have to be less dense than the air on Earth, and it’s hard to see how such an object would hold together while it tumbles through space.

Here Loeb brings into play some of his personal experience. He recently participated in a privately funded project to conceive of and then design a probe that could be sent to a nearby star and return signals within a human lifetime. The probes that we have already sent out of the solar system, the Pioneer and Voyager programs, and more recently the New Horizons flyby of Pluto, all depended on chemical rockets to launch them and set their initial course, then used gravity assists from the outer planets to speed them on their way. They will take centuries, if not millennia, to reach any stars in their paths.

The Breakthrough Starshot program that Loeb participated in envisioned instead a small electronics package, a “Starchip,” attached to a lightsail. This vehicle could be put into space near Earth and then propelled by a laser fired from the planet’s surface and focused on the sail. A sustained laser blast could accelerate it to a high fraction of the speed of light. The sail would be very thin and light: think of the metal coating on a Mylar party balloon. It could take the package to the nearby star Proxima b in about twenty years. As the Starchip passed through the Proxima b system it could record images of the Earthlike planet that we know orbits this star. The chip could then send these images back to Earth in the 4.2 years that light (and any radio signals) from Proxima b takes to reach us. The beauty of the program is that the main capital and operating costs, including fuel, are in the Earth-bound laser, while the individual probes would cost almost nothing by comparison. So the program could send out hundreds or thousands of Starchips to different nearby star systems.

With this background, plus his lifelong interest in the search for extraterrestrial intelligence to begin with, Loeb was primed to see ‘Oumuamua as some form of lightsail: one hundred meters wide and perhaps no more than a millimeter in thickness, fully expanded, very reflective, and tumbling slowly. It might have been sent into our solar system as part of an alien Starshot program. However, from the mechanics of its parabolic orbit and its presumed entry speed, Loeb and other scientists think ‘Oumuamua must have been moving at the average speed of most of the stars rotating in the galactic plane—and then our Sun, which is moving a little faster than average, scooped the object into its gravity well and redirected it to who-knows-where. So, in that interpretation, ‘Oumuamua might have been an interstellar navigation buoy or repeater station, instead of an aimed probe.

As Loeb describes the situation, most astronomers consider ‘Oumuamua to be a natural object, and they cling to interpretations of its orbital deviation that involve either a hydrogen iceberg or some kind of super-lightweight mass that still has the internal strength to tumble and not fall apart. He believes these scientists resist the evidence of ‘Oumuamua’s artificial and possibly technological nature because the search for extraterrestrial intelligence (SETI) has leaves a bad taste with true scientists. The notion of alien intelligence brings to mind too much science fiction full of little green men, bug-eyed monsters, and evil space invaders, as well as too many years of aiming radio telescopes at various stars and listening for messages that never come.³

I have always believed that, in a universe filled with billions of galaxies and trillions of stars like our Sun, and now with growing evidence that many of these stars have Earthlike planets in their habitable zones, it would be the extreme of hubris to think that ours is the only planet to develop and support life, or that human beings are the only intelligent, tool-building and -using, and soon to be spacefaring species in all of that vastness.

I find Avi Loeb’s reasoning to be persuasive. We have just detected the handiwork of intelligent aliens that passed unannounced through our system. Maybe it was a lightsail or an interstellar beacon disturbed by the Sun’s gravity, as Loeb suggests. Or it could also have been a cargo cover, a blown hatch, or debris from a larger ship that suffered some terrible accident. All of that would be unprovable speculation. But what I no longer think is that ‘Oumuamua was an extrasolar asteroid or comet—not even one made out of pure hydrogen ice.

1. Much of Loeb’s book is autobiographical, demonstrating his solid scientific background. It also gives a detailed history of the science of astronomy in relation to comets and asteroids and various professional inquiries and disputes about the search for extraterrestrial intelligence, which makes for fascinating reading. But I’ll try to focus here on the issue of ‘Oumuamua itself.

2. The inverse square law says that the amount of radiation from any point source that broadcasts in all directions decreases proportionally with the square of the distance from it. So, if the strength of a light is, say, 1,000 lumens at a distance of one mile from the source, then it is just 250 lumens at two miles (one-quarter being the inverse square of two), and only 110 lumens at three miles (one-ninth being the inverse square of three). You can test this by measuring the amount of light from a lamp as you walk away, from standing next to the bulb to standing across the room.

3. But, as Loeb points out several times in the book, many physicists devote their careers to studying the extra dimensions—beyond the three that we know of, plus time—needed to support string theory, or the nature of the multiple universes that support probability theory and the fate of Schrödinger’s cat. And we spend hundreds of millions of dollars on particle accelerators and experiments to prove the supersymmetry underlying quantum mechanics. These are just beautiful ideas without, so far, any hard evidence to back them up. And here a piece of alien technology—although the evidence is debatable and requires some thought and analysis—has just floated through our solar system.