To put the universe into perspective, lets talk about stars. When you look up at the night sky on a dark night, you can see a painting of sparkling lights, slowly drifting across the sky. What you’re looking at though isn’t really a fair picture of the universe. It’s more like a fair picture of the “local group”; stars that are all within about 1000 light years from Earth. The rest are too far away to see, too dim to see even if you looked, or hidden behind other stars that are closer to us: you’re only seeing about 1 hundred millionth of the actual stars in our galaxy on the best of nights (about 2500 stars). For our entire universe however, the number of stars is somewhere between 1022 to 1024. That number is absolutely incomprehensible for most people, so think of it this way: for every grain of sand on every beach on Earth, there are 10,000 stars in the universe. 1 grain of sand equals 10,000 stars.
So if there are so many stars in the universe, there must be planets just like Earth as well, right? There’s a lot of long winded math involved but to cut to the chase: scientists’ best (conservative) estimates put the amount of Earth-like planets at 100 billion billion. To carry on with the sand analogy: 1 grain of sand equals 100 Earth-like planets.
Hold on just a second though, there’s no guarantee that every Earth-like planet has intelligent life on it. We still don’t understand the full processes of life, so if we’re conservative with our assumptions and say just 1% of all those Earth-like planets have intelligent life, that means 10 million billion intelligent worlds are spread throughout our universe. In the Milky Way Galaxy, that equals around 1 billion Earth-like planets and around 100,000 intelligent worlds. If that’s the case though, then where are all the aliens?
This is the Fermi Paradox: with such high estimates of intelligent life in our universe, why haven’t we noticed them? Our Earth is only 4.5 billion years old, and our best estimates put the age of the universe at around 13.8 billion years. Now the first few billion years in the universe there was no way life (at least life like ours) could have existed. Everything was forming still; very radioactive and very hot. But that still leaves billions of years to be accounted for: could aliens have matured in intelligence during that time?
Using the Kardeshev Scale, we can measure the ‘maturity’ of a species by their ability to harness the energy around them. The scale starts at 1 and moves to 3, each number representing the effective ‘reach’ of the species.
A 1 on the scale means we can fully harness energy from our host planet.
A 2 means we can fully harness the energies of our host sun.
A 3 means the we can fully harness the energy equivalent to the entire Milky Way Galaxy.
By using Dr. Sagan’s further classification formula, we can work out where humans stand on the scale: around .7.
So, humans have a long way to go before we can be considered any sort of authority in our universe. There’s also the concept of “filters”, which are the natural barriers to life that essentially filter out entire worlds through common evolutionary leaps. If Earth has made it through filters before, have we passed the final filter which would be the ultimate threat to any civilization, only allowing an exception by way of chance?
Are there even any aliens out there, or are we the first in our universe?
Are advanced aliens watching us, waiting for us to develop further, or are we the proverbial ant hill that an explorer simply walks by, too small to be of any notice?
Are we just living in a hologram world programmed by some higher being, or are lizard people pulling the strings?
So many questions that are very entertaining to think about, and for now, we have all the time to ponder them. If you follow anthropics, you’ll be just fine thinking on our species as a rarity.
Read more at http://tv.bamargera.com/explore-the-mysteries-of-alien-lifeforms-by-studying-a-mindblowing-theory-the-fermi-paradox/?4jaOFhwCBAZyKFTQ.99