I've never seen an alien.

I saw a UFO in early 1996 when I was walking across a field on my way to working a graveyard shift at a TV station.

Something with lights was hovering over the city of Calgary near midnight in mid-winter, then it moved VERY fast and was quickly out of sight. I've never seen a plane or jet move so fast.

I don't believe it was from another planet, I think it was probably terrestrial. It could have been some kind of military aircraft that the public hasn't been informed about, but I don't know for sure.