Are Aliens Calling Us From Proxima Centauri?

Mysterious radio signal coming from a potentially-habitable star system? It’s almost too good to be true. And it is.

I’ll just go ahead and say it right now and get it over with: it’s not aliens. It’s never aliens. We’ve been listening for calls from E.T. for well over half a century now, and every single mysterious radio signal has turned out to be…less than mysterious.

But could this be it? Could this be the one to buck the trend, and be our first communication from an alien civilization?

First, let’s be cautious about the source. I mean about the news, not the radio signal. The story first appeared in The Guardian and Scientific American, both reputable publications. But the story was based on a leak from someone in the Breakthrough Listen team, the collaboration funded by billionaire Yuri Milner to piggyback on radio telescopes around the world to listen for aliens calling.

There is no paper. There are no data. There is no peer-review. There is no discussion about what they’ve found, the work they’ve done, and assumptions they’ve made, or the analysis performed. All we know is that they caught a bright radio signal coming from the vague direction of Proxima Centauri a few times in the summer of 2019 – note that they didn’t see the signal every time they looked, only sometimes.

The signal is at a frequency of 982.002 megahertz, which is generally free from human-made interference, hence it piqued the interest of the researchers. But while eager E.T. explorers want to point to Proxima b as the source, apparently the signal changed frequency in a way incompatible with the way that planet orbits its star.

And that’s it. That’s literally all we know.

Here’s the thing. Even if we’re never, ever able to come up with an explanation for this signal – even if we rule out every single known human and astrophysical source – it still doesn’t mean that this is a sign of alien intelligence. Failing to come up with an explanation does not give you permission to identify a signal as produced by aliens.

That’s because, being intelligent creatures, aliens are in theory able to generate any kind of signal you could possibly want. Anything you find mysterious in the night sky could be explained by aliens, and so that makes it useless as a scientific hypothesis to explain an unknown signal. To properly hunt of aliens, you have to predict what kind of evidence you expect to find, then go looking for that.

And that’s why I’m entirely confident in saying that even if we never explain the origins of this signal (which is itself highly unlikely), it’s still not aliens.