After half a century, we may finally have an answer to physicist Enrico Fermi’s famous question about alien civilizations: “Where are they?”
Fermi’s point was that such civilizations likely arose millions of years ago, and should have spread across the galaxy by now. Yet we see no sign of them — and we’ve now been looking for more than half a century.
Earlier this month another Italian-born physicist, Laval University’s Ermanno Borra, published an article claiming that he and graduate student Eric Trottier have found evidence of signals — regular light spectrum variations or, in effect, colour changes — from just 234 stars out of 2.5 million scanned. What’s more, he argues that these signals are aimed at us by “extraterrestrial intelligence” and intended “to make us aware of their existence.”
As a recovering science fiction author, I both want to believe it and refuse to believe it.
Never mind Borra’s scientific arguments, which are beyond me. He’s a respected physicist who’s been publishing peer-reviewed articles for more than 40 years. Let’s suppose he’s right.
Borra’s 234 stars are all very similar to our own sun: not too big, not too small, not red giants or red dwarfs. Presumably they’re at distances of scores to hundreds of light-years from us.
Spamming the stars
So why would 234 civilizations spend decades or centuries spamming a silent star like ours, just because it was roughly the same type as theirs? Were they sending a patient “wakey-wakey” because in their alien wisdom they knew we’d eventually quit chipping flints and start building lasers?
My own suspicion is that if aliens are out there, Borra and Trottier are just eavesdropping on them. They are no more contacting us than adults at a party want to rouse the toddlers upstairs and invite them down for a drink.
I have read far too many alien-contact novels to think that we would even recognize an alien when we met one. The ants of Peru have no idea that they once lived in the Inca empire, or that the alien invader Francisco Pizarro overthrew the Incas and took over. In 500 years, no one has thought to send a signal to Peru’s ants about these events. If they have asked us, “What’s going on up there?” we have somehow missed it.
A signal or a porch light?
These 234 alien civilizations could be equally uninterested in us. Interstellar laser signals may be just their porch lights; their direct communications may use technology we don’t understand, any more than users of smoke signals would understand the internet.
Even here, I’m using human-based analogies that may be totally irrelevant to real aliens. We simply can’t assume that other planets routinely evolve life that turns into little green men, or Vulcans, or anything else we’d recognize as an organism that thinks and acts like us. Still less can we assume that such organisms would find our recent technology, like lasers, useful for their purposes.
But just for fun, let’s suppose the 234 signals really do come from alien civilizations that want to contact us, and then consider the implications.
First, we can conclude intelligent life must be very common and arise on many planets around stars like our sun.
Second, civilizations must last a very long time and communicate with one another; eventually they share a lot of technology, even if they don’t physically travel between stars.
And apparently a lot of these civilizations (though likely not all) think that signalling to newly advanced species is worthwhile, even if answers will take centuries or millennia to arrive. Recognizing a laser signal in the interstellar background noise might be considered a qualification for membership in the club. So they all fire off lasers at promising solar systems (and they would surely have identified our system’s planets). However much energy these signals might require, the aliens would have plenty of it.
Suppose we ignored Stephen Hawking’s warning about answering an alien message, and sent a laser signal back to the nearest civilization. We might even pack our response full of data about us, just to speed up a very slow conversation: We want to be your friend. The aliens might look at our effort the way you look at your three-year-old’s art work on the refrigerator door: sweetly primitive and adorable.
And suppose they then sent back the basic Application Form for Galactic Empire Membership, complete with instructions for adopting alien technology, the histories of 234 advanced species and some samples of their culture.
Assuming we could even understand what they were talking about, we would likely be overwhelmed. Our own sciences would grind to a halt while our scientists puzzled over the new data. And our own cultures might be drowned in the tsunami of alien cultures.
That, not conquest, would be the real alien threat. We are unlikely to have anything they want, least of all if it means schlepping hundreds of light-years to come here and take it from us.
A wiser strategy might be to shut up and listen. One survey turned up all these possible civilizations, so more surveys are called for. (If 2.5 million stars have 234 civilizations, and the galaxy has 100 billion stars, we must have a lot of company.)
If we can pick up a split-second laser burst, maybe we can pick up other transmissions as well, including some that carry more information. If we can decipher them at all, we can learn more.
Maybe the aliens have anticipated our caution and prepared simple packages of basic information that we could understand more easily. We’d still be like toddlers at the top of stairs, baffled by the grown-ups’ conversation. But we’d understand some of it, and begin to get a sense of what we’d be getting ourselves into.
And if they really are out there, the sooner we’re ready for them, the better.