re: Tom DeLonge, his company "To The Stars" and the Aliens phenomenon.

There are many different species and factions:
Humans from prior space-fairing civilizations (nordics, hindu, and mayans)
Avians who have similar proportions to humans but have bird heads (these were feathered gods in ancient times)
Reptilians (snake people) that sorta look like Sleestacks, but more refined
Grays, the classic looking aliens from tv and movies that are short and look like children. They are essentially a slave species used to man ships.

Flying saucers are essentially scout ships/small transports.