The ongoing search for intelligent (or any) life in the universe
The past few years have seen an explosion in the number of exoplanets that we’ve discovered. In fact, it seems that almost every star we look at has one or more planets whizzing around it. For those of us of a certain age, it’s hard to believe that before 1995, the mere existence of exoplanets was 100 percent science fiction!
Of course, we knew they had to be out there. There are just so many stars. It would be unimaginable that ours was the only planetary system in existence. After all, there’s not anything special about our Solar System; just a bunch of gas and rocks flying around a rather mediocre star out in a nondescript arm of a fairly typical galaxy. We just had to keep looking…
Now, with so many confirmed exoplanets out there (more than 3,500 as I write this) and so many stars remaining to be looked at, the question becomes, “Where are the aliens?”
I mean, they have to be out there, right? Given the size of the universe, and the number of planets we know are out there, it seems unthinkable that we’re the only intelligent life in the entire universe.
This is known as “Fermi’s Paradox.” Named after famed physicist Enrico Fermi, this sums up the current state of the search for extraterrestrial intelligence: The place should be crawling with civilizations, but there don’t seem to be any of them anywhere!
Well, there are quite a few hypothetical explanations for this state of affairs. (Hypothetical, because we’ve never actually seen an extra-terrestrial civilization in any state, let alone after it collapsed.) So, maybe…
We’re the first. That seems unlikely, given the age of the universe.
We’re the last. This is a bit more likely, given the age of the universe. But, if that were the case, there should be some residual evidence that they were there at some point. (A really old/advanced civilization would have tried to explore the galaxy and left behind probes that we should have encountered by now.)
Advanced civilizations have a tendency to destroy themselves. Depressing, but likely. Our own civilization is only about 10,000 years old (if you round up a bit), and we’ve already got nuclear weapons, rampant Climate Change and only a half-hearted Asteroid Detection network. Add to this the fact that we really seem to enjoy killing each other and it’s not a good bet that we’ll make it to the 20,000-year mark.
We’re in a “zoo.” I’m not a fan of this one, but, many theorists think that we’ve not been contacted because the civilizations around us have decided that we’re too young, too dangerous or both. If we survive the next few thousand years, then maybe they’ll talk to us.
The Great Filter. Barring any other explanation, there may be some unknown barrier (a “Great Filter”) that all advanced civilizations must pass through to become stable and long-lasting. Again, since we have no examples to go by, we have no idea what this might be. But, given the silence we hear in the universe, it seems to be pretty effective at its job. (Personally, my favorite explanation for the Great Filter is “Galactus.”)
However, there are a couple of recent developments that have given hope to the SETI (Search for Extraterrestrial Intelligence) folks.
First, is the mystery of “Tabby’s Star” (which I discussed a couple months back). This unusual star is surrounded by something (or somethings) that has been causing the star to dim by an unusual amount over the last 100 years. At this point, they still don’t know what it is, but “Alien Mega-Structure” is still in the running.
More recently (literally, last week), a couple of Harvard theorists advanced the idea that Fast Radio Bursts (radio signals from another galaxy, lasting fewer than 5 milliseconds, yet 500 million times more powerful than the output of our sun) were actually being used to power light-sail vehicles across interstellar space!
These beams only intersect the Earth by accident, and only for the short time it takes to aim them correctly at the vehicles they are pushing through space. Such insanely powerful beams could easily push a massive ship (containing colonists maybe?) across the void at relativistic speeds.
Of course, it’s all hypothetical at this point. But, like exoplanets before, aliens have to be out there, right? For me, at least, the alternative is simply inconceivable. We just have to keep looking, listening, and sifting through the data.
Steven W. Disbrow is a programmer who specializes in e-commerce and mobile systems development, an entrepreneur, comic-book nerd, writer, improviser, actor, sometime television personality and parent of two human children.