Now that we’ve found another planet that is “just like Earth” the question is coming up: Is it populated?
(If you came here looking for a DC comics reference, this isn’t what you’re looking for. Stick around though. It’s fun.)
I once referred to the Fermi Paradox obliquely in the post https://wordpress.com/post/16293530/157/ about Alien Invasion several years ago. That post deals with all the reasons aliens would and wouldn’t bother with Earth. The Fermi Paradox says that the universe is so big and so old that if aliens existed, they’d have found us by now and said, “Hi!”
Well, the bad news is the Fermi Paradox might be right. The good news is that it’s probably not. Statistically, even if the chances of life developing on a given planet are one in a jillion, there’s billions of inhabited planets out there in the universe.
Seriously, we’re not alone.
Ignoring that Ed Snowdon tells us that aliens live under Earth’s crust, let’s leave the definition to mean species from other planets.
While extra-terrestrial life is a certainty, intelligent extra-terrestrial life is also a certainty. I mean statistically a certainty.
First, Earth isn’t rare. Earth 2.0(the nickname for Kepler 452b) might be 1400 light years away, but we’ll find closer ones. Planets are really small and don’t give off light. We’ve found very very few planets by ‘seeing’ them with a telescope. Most of those were in our Solar System. We discover most planets by occultation, meaning, we can detect a tiny dimming of a star when the planet passes in front of the star from our perspective. The odds of any given solar system being on the proper plane to produce occultation is very small. If we’re looking at a star’s north pole, we’ll never see a planet in orbit around that star pass in front of it. We pretty much have to be looking edge on at the star’s solar system to see an occultation.
We can also detect planets by wobble. As much as a star’s gravity keeps a planet in orbit, the planet’s gravity is always tugging slightly at the star, creating a wobble. For us to see a wobble, we currently need the planet to be massive, usually bigger than Jupiter, and close to the star.
As technology improves, we can see slighter wobbles, which means we can see the signs that smaller planets are out there. You need to understand this is very complex math and requires years of watching the same star. An astronomer on a planet ten light-years from Earth would have a damned hard time calculating that our sun has eight planets. After ten years, they’ll know about Jupiter, but Saturn would take decades to detect with any accuracy. Compared to the wobble on our sun caused by Jupiter, Earth’s gravitational effect on the sun would be negligible. Eventually they’d figure it all out. But the point is that we, when observing other stars, looking for planets, have to spend years, even decades to find them. That makes my more important point. There are lots of planets out there. The science and the statistics tell us they’re there. We just don’t know exactly where.
Now that we’ve established that habitable planets are common, we want to assume that all planets that could be inhabited are inhabited. Let’s just make that assumption, because, with the numbers we’re talking, billions of Earthlike worlds, whether a few or all are populated by some form of life isn’t terribly important. Important is acknowledging that some of them are.
After over a billion years of life existing on Earth, it’s been about 50 years since we managed to throw anything off our rock. There is only one significantly intelligent species on the planet. This basically means that no matter how common life is, intelligent life is far rarer. You might try to argue that humans have squelched out any competing species. That might be true over the past million years, but it doesn’t explain why no species managed to invent an iPhone before humans even evolved.
But, again, there are so many earth-like planets in our galaxy, some of them will have intelligent life. They will, that’s a fact. (Note that, for legal purposes, I only state opinions, so even if I say it’s fact, even if it’s actually a fact, I’m only stating my opinion. –see the side bar—>)
There’s still no guarantee we won’t kill ourselves off before we find a way to make it to the nearest other habitable world.
We don’t know what technology we can use to do that yet. As far as we know physics, there is no such thing as warp drive. There is a finite speed limit for a space ship that makes travelling light years simply infeasible. We don’t have the technology to get to the nearest stars, those less than five light years away. By the time we find speeds that would get us there in less than a thousand years, the speeds we’d travel would tear any material we know about apart. So, until we develop warp drive no person will ever travel to another solar system.
There is the concept of putting travelers in cryo-sleep, basically stopping their aging while they travel. Still, thousands of years. The best cars have ten year warranties. How do you trust a star ship not to break down over that time? Okay, so that tech is in the foreseeable future. Cryo-sleep and self-repairing ships might be possible in our lifetimes. Still: Thousands of Years. Let’s just say that, without some kind of Warp technology, interstellar travel is just not an option unless your planet is no longer habitable.
So, to continue this discussion, we have to leap to the assumption that warp technology is possible. If so, there might be thousands of civilizations bouncing around the galaxy, visiting new worlds and maybe spreading their species on new worlds.
The Fermi Paradox asks that if Intelligent Alien Life exists, why hasn’t it contacted us?
The real question is: Why would aliens want anything to do with Earth?
We’ve all seen the t-shirt or bumper sticker “Mean People Suck.” From an alien perspective it would just be “People Suck.” There is no benefit in engaging in commerce with a less evolved planet. We expect to trade our iPhones for their Hixoblups? Yeah, no. They won’t want what we can offer.
Raw Materials? Earth has lots of iron, gold, and water. Honestly if you can get around space easily, there’s no reason to deal with such pesky things as atmospheres and pesky natives when mining. Asteroids and uninhabite worlds are just so much easier to mine. Water is not rare. Iron is not rare. Gold is not rare. Nothing on Earth is worth putting up with humanity. I mean we still think there’s something to reality TV. Well, there’s something we might be good for. Aliens might have sensors set up to monitor us for their own ‘Stupid Human Stunts’ entertainment. It could be argued that the most significant human development for the purpose of perpetual posterity might be cat videos.
Basically, unless they think our culture is the bee’s knees, any intelligent alien species is going to avoid us like the plague we are.
Even if the Aliens just need a new world to colonize, they have better options than Earth. Assuming intelligent life sticks around on Earth until the oceans boil away in four billion years, intelligent life was only on Earth for half of it’s habitable time. That means there are other worlds to move their civilization to that don’t require them to deal with pesky indigenous intelligent species.
Basically, the Fermi Paradox is too simplistic. It’s not that alien’s aren’t out there, its that, any life-form smart enough to develop space travel is also smart enough to avoid any species as annoying as humanity. We can’t see them because we just can’t see that far yet. They don’t want to see us.