no thats imposible..
Why would it be impossible ? We hardly know what lies in our ocean, how would we know what lies beyond this planet ?
because I had never seen it
How about god, do you believe that he exists ?
I certainly believe in the existence of god ..
because obviously what he has created in this world
I personally do believe in God but, I don't believe that aliens are really exist. And btw, aliens and God are totally a different things.