News comes at us in salvos these days, like meteorites striking the surface of the moon, the small ones that raise some dust interspersed with the big ones that carve out craters. It can be hard, seeing them approach, to know which will be which. Last week’s shower of information, for instance, brought, along with word that bacon is bad for you, and Cruz is crazed and Rubio is cynical (or is it the other way around?), the additional casual news that, oh, yes, astronomers may have discovered an alien megastructure built by an advanced civilization orbiting a nearby star.
The arguments for the alien whatever-it-is, it turns out on deeper inspection, are inferential and deductive to the point of conjecture and speculation and had, frankly—as the astronomers themselves agreed—been rushed toward the public eye before they had really passed the scrutiny of expert ones. But if it was far from a fact, it was just as far from a joke. Basically, the light of a distant star—KIC 8462852, if you’re keeping score—seems, on inspection by NASA’s Kepler space telescope, to be periodically interrupted by something passing in front of it, and whatever it is passes so strangely, so spasmodically, that it suggests something made rather than something found—it doesn’t look like a natural object orbiting its star in a dutifully natural way.
Astronomers, as you may recall, have been “spotting” more and more distant planets circling distant stars in this way for a while now: roughly speaking, they locate a dip in the light of a faraway star and then, hypothesizing that the transit of a planet in front of it is causing the dip, can chart a “light curve”—beautiful phrase!—from which they can deduce the passing planet’s size and even its shape and speed. In this way, they’ve identified almost two thousand exoplanets, as they’re called. In this new case, though, the flutter in the starlight rises and falls in peculiar ways that suggest something big enough to block vast areas of light while being irregular enough in its transit to suggest something made and manipulated more than something dutifully following a near-Newtonian path. It might well be, the astronomers quickly add, a cloud of comets, or something like that, but it’s hard, then, to figure how they got so big so fast and why they move so irregularly.
Puzzled, some astronomers brought up a strange but enticing hypothesis. It’s long been conjectured that a “Type II” civilization—one that, on the Kardashev scale (neat term), can harness all the energy from its nearby star, not just of its home planet,—would build “Dyson spheres,” named after the astronomer (and New Yorker contributor) Freeman Dyson, who suggested such a thing half a century ago—solar-collecting devices that would fully harvest the energy of its sun for the use of the smart people on the planet. What if what was in transit around KIC 8462852 were just such a frame? It would be big enough, strangely shaped enough, and perhaps irregular, or non-regular, enough, for some engineer to have positioned it for maximal effect, or, sighing, for two astronauts to climb up on it to fix some broken bit (an adventure which could then later be made into a summer hit at the exoplanet’s multiplex).
Veterans of could-it-be-aliens moments may recall the Wow! Signal, of 1977, also a supposedly solid lead that there was Someone Out There. Detected by the “Big Ear” radio telescope then being used by Ohio State University—sorry, The Ohio State University—it bore witness to a strong, sudden, never-replicated burst of radio waves at a frequency that seemed highly unlikely to have naturally occurred. It was exactly as if, on a night by the ocean filled with fireflies and distant stars, the beam of a searchlight swept—narrowly, fiercely, and definitely—right across the bluff. Even if you never saw it again, you’d feel certain that someone had cast that light. (It’s called the Wow! Signal because that’s what the astronomer who spotted it wrote in the margin along the data.)
The first thought for any veteran Wow-watcher was to wonder if this might be another Wow! from the same part of the sky. So far, it doesn’t seem to have been, but a perhaps-too-ingenious science blogger has pointed out that if the universe is a Poincaré Dodecahedral Space—and why shouldn’t it be?—then it would, in effect, fold over on an accommodating point, and the Wowers! and the starlight-flutterers might well be the same people, still trying to send us a message, like a fifteen-year-old texting home repeatedly in increasing aggravation. (“Dad???? You There????? ANSWER YOUR PHONE???!!!”)
Two significant things break the spell of speculation—one is that, whatever is really going on over by KIC 8462852, the search reminds us of the awesomely inferential quality of so much good science. Chains of reasoning from secondary causes are often essential to making big discoveries. Neutrinos, in the news recently thanks to a Nobel Prize, were first detected only inferentially. We reconstruct lost animals from teeth and jaws—the proto-Sasquatch Gigantopithecus has been identified by lots of teeth and a few mandibles. A child’s finger bone, mined for DNA, identified an entire species of hominin, Denison man. To the confoundment of creationists, this small evidence is not the same as little evidence—sequences of reasoning based on a transit or a tooth usually produce other kinds of evidence, or more bones. All is but a woven web of guesses, the early philosopher of science, Xenophanes, wrote—but if the weaving is taut, the web holds water, or stars. The astronomers studying KIC 8462852 are patiently and diligently trying to weed out all the other candidates to explain what’s perturbing its light. Positing a giant Rube Goldberg device is science, exactly on the Sherlock Holmes principle—that when everything else must be discarded, what remains must be true. The great likelihood is that the astronomers will settle on another explanation. If they can’t, then, well—Greetings, Klingons!
The other inescapable reflection is that, as we look outward, others must be looking inward—at us. The one thing, the only thing, we can say for certain is that any civilization worth looking at would almost certainly be busy looking back. They could be speculatively inferring from our utter absence of Dyson spheres—from the apparent absence of any visibly fretful activity, aside from the rare amusing atomic explosion, which they might see as a clever but not terribly threatening piece of ‘primitive’ technology, rather as we see an aboriginal elephant hunt—that we are, at least, at peace: a not-quite Type I civilization, humming along in serene ignorance. They would not see our agitation and our crises and our apocalyptic moments, our threatened extinctions and ecological panics, any more than we have ever been able to see the real crises and dynamics of the “simpler” people we patronize. (The paradisiacal Tahiti that Gauguin visited was a land already despoiled and corrupted by colonization.) They might look down at Earth and sigh, during some funding sequester that is holding back the completion of the vast Chancellor Mortak Memorial Energy Project, and think, oh, to be that innocent again!
One other scientific possibility must be considered: the designation KIC 8462852 calls to mind asteroid B-612, the small star-home that Saint-Exupéry’s small star hero lived on before his flight to Earth. Perhaps the forms occluding the star with such beautiful irregularity are the wings on the flight of birds that brought the Little Prince to Earth, which would surely transit the starlight with exactly the right kind of fluttering irregularity. Some of us wouldn’t find that the least surprising.
