1st question answer: The Protestant Believers separated themselves from the Catholic church because of the Wrong Beliefs of the Catholic Church. And According to the Bible, we must go away from the People who claim that they're Godly but denies its power.
2nd question answer: There's no written about alien things in the Bible. But Alien is similar as pilgrims or a traveler. I am a pilgrim of this earth because my house is not here it's in heaven.

This is my own Opinion. Thankyou! God bless!

Sorry for the wrong grammar.
@truth-be-told