It’s been over a month since my trip to KIC 8462852, better known as Tabby’s Star. And yes, my trip was totally for real. I was actually there and saw the alien megastructure for myself. You can trust me on this.

Anyway… I did a lot of research and reading to prepare for my trip, and I noticed a common theme in almost all the papers and articles I read: whatever’s happening to Tabby’s Star, it was very easy for us Earthlings to miss. In fact, it almost was missed.

Tabetha Boyajian herself (for whom Tabby’s Star is named) initially dismissed the star’s anomalous light curve as faulty data. And that could have been the end of it, no further investigation required.

It’s almost dumb luck (plus the persistence of a few citizen scientists) that Boyajian and others ended up taking a second look at that “faulty” data and realized it wasn’t a problem with the telescope, that something legitimately weird was going on.

Enrico Fermi Still Whats to Know: Where Is Everybody?

I’m bringing this up because I think it has interesting implications for the Fermi Paradox. Circa 1950, physicist Enrico Fermi argued that advanced space faring civilizations should be out there somewhere, and furthermore Fermi said we should have seen them or heard from them by now. So where is everybody?

Now I don’t want to oversell my point here, because there are a lot of possible answers to Fermi’s question. Maybe we really are alone in the universe, or maybe intelligent life is less common than Fermi assumed. Or maybe intergalactic law forbids making contact with primitive worlds like Earth.

But it’s also possible—in my opinion, very possible—that evidence of alien civilizations is there, but we’ve just missed it. Maybe we haven’t been looking in the right places, or maybe we haven’t been looking for the right things. Tabby’s Star is a perfect example. I don’t know if aliens are responsible for what’s happening to Tabby’s Star… wait, I mean I do know, because I was there and saw the aliens. No really, I did.

Umm… anyway… even if there weren’t an alien megastructure, the story of Tabby’s Star should tell us something about how easy it is for us to overlook what’s happening right in front of our eyes—or what’s happening right in front of our telescopes.

On Monday, I arrived at KIC 8462852, better known as Tabby’s Star, and discovered that yes, the aliens really are building a megastructure. My next question is: how long has this been going on?

These aliens are not turning out to be all that friendly. Fortunately, there’s been some investigative work done back on Earth.

Astrophotography has been around for well over a century now. Even though no one paid much attention to Tabby’s Star until recently, that region of the sky has been photographed before. So following the publication of Tabetha Boyajian’s WTF paper, astronomer Bradley Schaefer started checking those old photographic plates.

And according to Schaefer’s findings, Tabby’s Star has been decreasing in brightness since at least 1890. It would seem the megastructure has been growing in size, obscuring more and more of the star, for quite some time now.

But can we trust the accuracy of those old photographic plates? According to astronomer Michael Hippke and colleagues, no. No we can’t. The degree of uncertainty is too high, Hippke claims, to make a conclusive determination about Tabby’s Star’s brightness over time.

There’s been a pretty intense argument between Schaefer and Hippke ever since. If nothing else, it’s an excellent example of how scientists debate each other. Click here to read Schaefer’s side of it, and click here for Hippke’s.

So if Schaefer is right, construction of the megastructure may have been underway circa 614 C.E. (that’s 1890 C.E. minus the 1276 years it takes for light from Tabby’s Star to reach Earth). And if Hippke’s right… well, who knows when the aliens got started? They’re certainly not telling.

So I’ve flown my spaceship all the way out to KIC 8462852, better known as Tabby’s Star, and what do you know? The aliens really are building a megastructure out here.

This whole situation is pretty weird, I know; but the weirdest thing is that when I check my ship’s sensors, I can’t detect any thermal emissions from the megastructure or any of the spaceships involved in constructing it.

The lack of thermal emissions (or the lack of an “infrared excess,” as the experts call it) is one of the main reasons why Tabetha Boyajian and other legitimate scientists don’t really buy the alien megastructure hypothosis.

Think about it. If Tabby’s Star hosts an active work zone, with spaceships flying around and construction workers welding space girders and stuff, you’d expect all that activity to produce some heat. Even without the construction activity, the megastructure itself should be pretty warm due to the star it encircles.

And all that heat should be detectable in the form of infrared radiation. But whether you observe Tabby’s Star with a telescope back on Earth or the sensor grid of my imaginary spaceship, the total amount of infrared light is exactly what you’d expect from an F-type main-sequence star. No more, no less.

Since I’m here, I decided to ask one of the alien construction workers about this. Here’s what he told me: “Yeah, we been masking our thermal emissions. What of it? We don’ts wants nobody snooping in our business. Now scram, smelly human!”

Not exactly the answer I was expecting, but I guess I’ll take what I can get.

P.S.: If you want to learn more about Tabby’s Star and how citizen science helped uncover its mysterious behavior, I strongly recommend this SciShow interview with Tabetha Boyajian. That’s where I first learned about the “infrared excess” issue that I discussed in today’s post.