The probability of there being life outside Earth FAR outweighs the probability of us being in the exclusive club. The Drake equation often offers an avenue for discussion regarding this matter. It calculates that there should be 10~ intelligent civilizations in our galaxy alone. Disregarding that the Drake equation may be based on conjecture, I'll show you guys that believing that we are the only lifeforms in the Universe is almost madness:
There are (rounded down) 100 BILLION GALAXIES in the Universe. The Milky Way is our galaxy. In those 100 bn Galaxies, there are on average 100 BILLION STARS (rounded down, heavily) per galaxy. For the sake of ease and being conservative, let's assume that on average that there is 1 planet orbiting each star.
So, let's do the math!
100,000,000,000 * 100,000,000,000 * 1 = 10,000,000,000,000,000,000,000
For those non-believers who haven't done the math, this number is 10 sextillion.
Now obviously the first objection is that but not all planets are capable of housing life. Astute observation! Let's add an extra probability function.
What number should this be? We'll try a few common numbers.
1 Million.
1 Billion.
1 Trillion.
10 sextillion / 1million = 10,000,000,000,000,000
10 sextillion / 1billion = 10,000,000,000,000
10 sextillion / 1trillion = 10,000,000,000
Subscribe to whichever probability you would like to add into the equation, I think the numbers do the talking. Oh, I forgot to mention this is a conservative estimate based on current knowledge.
We'll assume for the sake of argument that one agrees with the Drake Equations calculation of approximately 10 intelligent civilizations for our galaxy. We'll also assume that the Earth is in the center of our galaxy (for easy working). We'll also assume that the Milky Way is flat. (Like a piece of paper)
The diameter of the Universe has been estimated to be 100,000 light years across, BUT let's assume that the universe is like a piece of string, and we'll even treat it like a number line.
If there are 10 intelligent civilizations, including Earth, then 100,000 / 10 = 10,000 light years. This is a VERY VERY conservative approximation of the hypothetical distance between the next potential intelligent civilization (We've neglected unintelligent civilizations).
Current physics has taught us that it is IMPOSSIBLE to travel past the speed of light within space. However, we'll assume yet again that these intelligent civilizations are so smart that they can travel at the speed of light, 299 792 458 m / s. It would take them 10,000 light years to reach us. To put this into context, they could travel from the Earth to the Sun in 8 minutes.
So, just let this sit with you. If there are intelligent civilizations capable of travelling at the speed of light, the chance of them reaching Earth are virtually impossible.
How would humanity handle it? Chaos. It would be a huge wake up call and some people probably wouldn't be able to accept it.
What would they look like? Well, if you follow evolutionary theory they'd develop to suit their surroundings. So, I guess be creative and change the looks of us.
That concludes my essay =,=