If you’ve ever looked up at the night sky, you’ve probably had the opportunity to take in the vastness of space. You’re looking at stars so far away that it takes years upon years for light to reach your eyes. A star could die and you wouldn’t know for a thousand years. Just like we’ve only seen 5% of the ocean, we haven’t even come close to scratching the surface of what lies above (and in all other directions). As a result, you’ve probably given aliens a good thought. But are aliens real; and more importantly, if they are real, why haven’t we found them?
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Are Aliens Real? The Fermi Paradox
The universe is big. Like, we can basically assume it’s infinity big. Applying that logic, by the universal law of infinite probability, every permutation of every thing exists or has existed. So under that principle, where are the aliens?
(Also, as a side note, yes, under that principle that means there’s a rock somewhere in space that looks exactly like the Sporcle logo. But we digress. Don’t let it get to your head.)
But, even if there was a godlike alien race in a different galaxy, we’d probably never reach them (or vice versa). That’s because the universe is expanding. So given the constraints of technology and the speed of light, it could take billions of years to leave the local group. Even then, getting to other galaxies within the local group is super far off, farther than even just colonizing or terraforming other planets. Something that, as of 2019, doesn’t seem to be an idea that will be realized in our lifetimes.
So we’ll limit ourselves to the Milky Way (our galaxy), which is still so large your calculator will probably spit out numbers like infinity in terms of how many stars and planets there are. Conservatively, the estimate for planets in the Milky Way numbers around 100 billion. Knowing that there are likely more than that, we’ll run with these numbers. Even if just 1% of these 100 billion planets had life, we’d still have 1 billion life harboring planets. At least one other should have life? Or at least, should have had life.
The sheer numbers we’re dealing with encapsulate the Fermi Paradox. With such numbers, we should have gotten at least a whiff that we aren’t alone in the universe–so why haven’t we?
Colonizing the Galaxy
To save you the numbers, if we made a really good effort at colonizing the galaxy, sending ships with colonists to planet after planet just to put a human footprint on as many planets as possible, we could reasonably colonize the Milky Way quickly. Like, between 5 and 50 million years quickly. Considering that the Earth alone is almost 5 billion years old, a handful of million years is next to nothing to the Milky Way being upwards of 13 billion years old.
Learn something: Why Is It Called the Milky Way?
Potential Answers About Aliens
We’re Really Young
You might like to think that humanity is really far along in terms of development. Which, yes, we’re pretty far from rubbing sticks together to make fire. But, let’s be real, within the last 100 years we had weapons of mass destruction pointed at each other because we couldn’t decide on whether or not capitalism or communism was the spawn of Satan. We also still are fighting about climate change and the efficacy of vaccines, as well as having violent conflicts about race. Anyway, suffice to say that we still have a long way to go.
Perhaps we’re just not there. Our technology is too primitive to communicate on an inter-planetary scale. If you tried to contact all your friends with a ham radio and they all had smartphones, they probably wouldn’t receive any of your messages. Despite the fact that your friends are very much alive, you’d probably feel alone with your radio. It could be the same; our messages out either haven’t covered enough distance, or we’re not putting out the right signals to contact alien life.
If you’ve seen the Kardashev scale you’d vaguely know of three civilization categories, aptly named Types 1, 2, and 3. A Type 1 civilization can use and store all the energy on its planet, where 2 has control of its star, and 3 has control of its galaxy. For perspective, humanity isn’t even a full Type 1 civilization yet. We might get there in a couple hundred years according to Michio Kaku, though.
The Great Filter
Just like the dinosaurs were wiped out and just like the Plague cleared out swathes of Europe, maybe it just isn’t likely for life to last very long. After all, 99% of all life that has ever lived on Earth is now extinct, and on a cosmic scale, humanity doesn’t really have the odds in its favor.
Maybe aliens, like we are doing so now, wiped themselves out with climate change. When we first tested nukes, we had to ask if we would set the atmosphere on fire (math said we wouldn’t). We’re not going to go through all the weird ways that could exterminate all life or prevent them from wanting to explore the stars (like a Matryoshka Brain) because that’s a lot of time. But suffice to say that there could be a technological singularity we don’t know about.
Some planets may harbor life, but life itself can’t really get off of it. Think about how expensive it is to send things into space. It can cost up to $14,000 to send a single pound into space. So even simple satellites would cost tens of millions just to get up into the void.
Imagine a planet like a super earth; basically a really big version of Earth. Think about how much in raw resources it would cost to send even a minuscule amount of stuff into space.
While we doubt aliens are slinging US dollars around, the point here is that space exploration is expensive from a resource standpoint. And we can’t all be Jeff Bezos or Elon Musk.
Aliens Don’t Want to Be Found
That, or we don’t want to find aliens. We’re not even a Type 1 civilization as we’ve discussed before; so a Type 3, galaxy controlling, society might seem like deities to our tiny brains.
Maybe they’ve figured out some system where they have to get resources from life harboring planets. Tinier Type 1 civilizations would get stomped by these godlike beings, the same way we stomp on animals on Earth to get resources. Their needs or wants simply do not concern us.
Humans love to think we’re at the center of the universe, but it’s also entirely possible we’re just not that interesting to life elsewhere in our galaxy. Why spend all your time and resources to get to primitive Earth, when there are perhaps many more exciting regions of the Milky Way?
They’re All inside Area 51
Need more alien anarchy to get through the day? Check out this quiz about aliens and movies here.
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