The wide variety of questions that can be entertained simultaneously in the human mind can be amazing in scope: “Was there fraud in the 2020 U.S. presidential election?” and “Did we detect an alien technosignature from the vicinity of Proxima Centauri in 2020?” are compelling in their own way, both impactful in their own way as well. But rather than delve into the minutia of political maneuverings, I’m more interested in this moment to offer some speculations regarding the possible origins of broadcasts from ET: a signal identified in 2020 and dubbed Breakthrough Listen Candidate-1 (BLC-1).
What we know so far of the received signals is relatively little but fairly significant. There were some narrowband transmissions at a frequency of 982 megahertz, which is a part of the radio spectrum rarely used by human-made transmitters. These transmissions were detected during five 30-minute spans across several days when the Parkes telescope was pointed at Proxima. Notably, the signal vanished when the telescope was pointed elsewhere in the sky. Over the course of the observations, the frequency of the transmissions increased, as though the source was traveling toward us—which could be explained by the orbital motion of a planet or moon, or even of a free-floating device moving closer.
The scientific community is quick to acknowledge that BLC-1 is likely to be terrestrial in origin. Currently, the BLC-1 discovery team is pouring over the Parkes telescope data, checking everything to rule out more common sources. At some point the team will publish its findings. What if they conclude that the signal is extraterrestrial in origin? While that won’t necessarily mean that we’ve discovered ET, that’s a possibility worth considering.
But just for fun, let’s imagine that we have discovered an intelligent ET. What might this mean for the humans of planet Earth? There’s already been a lot of conjecture regarding finding a signal originating from the Proxima Centauri system. Would we be able to open a dialog with them? Would we be able to send them anything (artifacts? Technology?) through a Starshot lightsail probe effort? Would they want to communicate back with us? And along with those questions is the requisite surprise at the “coincidence” of finding another civilization at approximately the same level of technological development as are we, and so nearby.
I want to ask something different, pursuing a very different line of questioning. Let’s eliminate the coincidence factor. First, let’s disagree with the premise that we’ve found a civilization that is very near our own level of technological development, and second, let’s disagree with the premise that the sender of the signals is as nearby as the next star over. We can turn this into a little game of “What if?”
What if you’re an advance alien race, perhaps centuries more advanced than humans, and you wanted to communicate with us? You’d probably send a signal that would match our technological capacity to detect. Just because we receive a signal that seems like something we ourselves could transmit, it doesn’t mean the signal was sent by aliens at our equivalent level of technology at all.
Now, what if you’re an advanced alien race, and you wanted to contact us, but you also didn’t want us to know where you were? The simple answer is that you would put a transmitter somewhere other than your home world—or other than any place you value so that you could remain hidden from us. In fact, if you were really advanced, you might put a transmitter just in the next star system over from us. That might even make the signal that much more enticing, because we might conclude that we have the opportunity to get to know our nearby interstellar neighbor (when the fact is that the source intelligence could be hundreds or even thousands of light years away).
The “What If?” questions now become “Why?” questions. Why would an alien race plant a transmission device fairly close to Earth while keeping themselves hidden from us? The answer is obviously one of two possibilities: they either want to test us or trap us.