Sure. Just bring one in, dead or alive. Until you or someone else does this, or verifiably makes radio contact, you would not have enough evidence to constitute "proof".
No aliens do not exist if you think they do prove it but on the other had if don't believe that they exist I'm just saying that you can't prove if you think you can go to prison
no
There is no positive scientific way to prove/show aliens exist therefore no one knows how they eat
This question makes no sense. If people could prove whether or not aliens exist, then conspiracy theories would be a thing of the past. Again, this question makes no sense.
We do not know, we have yet to prove aliens actually exist.
If you mean aliens from another country, yes. If you mean aliens from space... not that anyone knows and has been able to prove. No proof aliens even exist, in real life. Just tall tales.
Well that I know of their might be living organisms that exist on mars, but aliens its possible.
Nobody knows the answer to this question because nobody knows if aliens actually exist.
There is no proof that aliens exist. I believe there is no such thing as aliens. Has anyone seen an alien ship? Has anyone seen an alien? No.
It could be possible if centauroid aliens exist that they may have six legs, maybe even 10 legs.
Nothing. There are no aliens known to exist.
There's no conclusive proof that aliens (in the sense of non-human extraterrestrial intelligences) actually exist. If they do, it's at least possible that they could be friendly.