To some, its obvious, we are not alone and Aliens do exist.
Everything from bizarre reportings from various credible sources, to most basic mathematical probability equations suggesting the existence of alien life, skepticism seems to be real answer of this question.
Whatever you opinions be, on the question, Do aliens exist?, below points will surely make you think more on your theory.
How big is the universe?
If we are the only beings or whether there are others too, we first need to know how big is the space we live in to.
Big bang, the galaxy we exhibit, is more of the OBSERVABLE UNIVERSE for us. it consists of all the atoms and elements from which light has been able to reach us since the evolution of Big Bang, about 14 billion years ago. But there might be more beyond the horizon, just as there is more beyond the horizon when we are observing the sea from a boat.
What is the possibility?
There might be more and more galaxies beyond the observable horizon, and the possibility being, existence of others living beings, spawning their own universe, disconnected from ours and having their own different physical laws. As we walk, they might be flying. As we talk for communication, they might be using some other means. As we are looking for them, they might be looking for us.
The universe that is observable by us is governed by same physical laws. But the same atoms can be assembled in many ways, which all of us has studied as part of our primary education. So, does it strike your mind that there might be another earth, even another avatar of you and me?
So how likely is alien life in this vast expanse?
But thinking that there might be life somewhere in the space does not mean that it is intelligent life, or life like ours or more supreme at all. Guess is, even if we detect an Alien, intelligent one, it will be some sort of electronic entity.
If we look at the existence of Life on Earth today, it took us some 4 billion years to reach where we are today, according to scientific studies. But if we look at our future, then likely within a few centuries, machines and Artificial intelligence will take us over, they will have billions of years to evolve ahead.
Are we aliens?
According to some scientists, Life initially began on Mars and space rocks caused an asteroid collision in our solar system smashing into each other and a chunk of life landed on Earth from Mars.
According to astronomer "Caleb Sharf", pieces of Mars can be found here on Earth and it is suspected that there are pieces pf Earth on Planet Mars.
On the other hand, some scientists believe that humans species are the descendants of 'Martian life' and got carried to Earth on an asteroid some billion years ago.
I am sure, the points cited above asks for some thought processing, i will continue my findings forms study sources in part2 of this article after completing my work there.
Note : I have studied all this data and findings in below mentioned sources, and wrote the above with my own understanding & language.