Retards
The burden of proof of alien existence belongs to those who claim so.
Actually, given that we exist, the laws of physics, nucleosynthesis, stellar formation and evolution and planetary formation appear to be universal, then the burden of demonstration falls to you to demonstate that aliens DON'T exist, since the evidence overwhelmingly supports their existance in very large numbers.
You are like a space enthusiast with Down's Syndrome, Raoul, you think it's so cool to be cool, but you don't have any of the prerequisite intellectual abilities to participate in any meaninful manner. Good luck at the special space olympics!
We're rooting for you. I'm wearing my extra special tin foil hat!